Olefin copolymer and process for preparing same

ABSTRACT

There are herein disclosed an olefin copolymer which comprises an olefin unit and a diolefin unit and in which a weight-average molecular weight is in the range of 200 to 800,000, the content of the diolefin unit is in the range of 0.002 to 30 mol%, and a ratio TUS/DOU between the total content of unsaturated groups observed in a molecular chain (TUS mol%) and the content of the diolefin unit (DOU mol%) is in the range of 0.001 to 200; an olefin graft copolymer obtained by the graft polymerization of this olefin copolymer and an olefin; a hydrogenated olefin copolymer and olefin graft copolymer thereof; and a process for preparing these copolymers. 
     These olefin copolymers are excellent in molding/working properties and have a good thermal stability, transparency and uniformity. Therefore, they are useful as a high-performance VLDPE, LDPE, L-LDPE and HDPE, and further useful as a novel branched propylene polymer, a thermoplastic elastomer, a compatibilizing agent for other resins, and the like.

TECHNICAL FIELD

The present invention relates to an olefin polymer and a process forpreparing the same. More specifically, the present invention relates toan olefin copolymer and an olefin graft copolymer having transparencyand uniformity which can optionally control the activation energy of thefluidization of a melt and in which high-speed molding is possible tolower a working cost, hydrogenated copolymers thereof having anexcellent thermal stability, and a process for efficiently preparingthese copolymers.

BACKGROUND ART

Heretofore, olefin (co)polymers have widely been used as general-purposeresins in many fields, but among these olefin (co)polymers, ethylene(co)polymers have the following problems and thus their improvement hasbeen strongly desired. For example, in a linear low-density polyethylene(L-LDPE) and a high-density polyethylene (HDPE), the activation energyof fluidization in a melting state is small, so that they are poorer inmoldability as compared with a low-density polyethylene (LDPE), and inparticular, a high-molecular weight compound has a substantial problemthat its moldability is poor. Furthermore, the ethylene (co)polymer hasthe problem of neck-in at the time of the molding of sheets and films,and moreover, the linear low-density polyethylene has a problem thattransparency and heat-sealing properties are poor.

As a method for solving such a problem, for example, there has beendisclosed an olefin copolymer having long-chain branches obtained byusing an α,ω-diene compound and a cyclic endomethylene diene compound(Japanese Patent Application Laid-open No. 34981/1972). However, in thisolefin copolymer, a diene component is concerned with the long-chainbranches and a crosslinking reaction simultaneously occurs, and a gel isgenerated at the time of film molding. In addition, melt propertiesinversely deteriorate, and a control range is extremely limited.Moreover, a copolymerization reactivity is also low, and owing to theformation of low-molecular weight compounds, physical propertiesinconveniently deteriorate.

Furthermore, another preparation method has been disclosed which ischaracterized in that when a non-conjugated diene compound iscopolymerized with an olefin, the polymerization is carried out in twosteps, and the content of a non-conjugated diene compound unit in ahigh-molecular weight portion is higher than that of the non-conjugateddiene compound unit in a low-molecular weight portion (Japanese PatentApplication Laid-open No. 56412/1984). However, in this method, along-chain branch is introduced into a high-molecular weight component,and therefore the increase in the molecular weight due to crosslinkingis noticeable. In consequence, insolubilization, nonfusion and gelationsimultaneously occur with a high probability, and a control range isnarrow and a copolymerization reactivity is also low, so that physicalproperties inconveniently deteriorate owing to the formation of thelow-molecular weight compound.

In addition, an ethylene-α-olefin-1,5-hexadiene copolymer obtained bythe use of a metallocene-aluminoxane catalyst has been disclosed(Japanese Patent Application Disclosure No. 501555/1989). However, inthis copolymer, a molecular-weight distribution is narrow, which isdisadvantageous to blow molding and film formation, and the copolymer isinconveniently devoid of thermal stability.

Moreover, also with regard to a propylene polymer, a resin design hasbeen made to sufficiently utilize characteristics peculiar to thepropylene polymer by imparting novel characteristics (particularly melttension), with the intention of achieving the wider application of thepropylene polymer. For example, in Japanese Patent Application Laid-openNos. 185490/1993, 194659/1993, 194778/1993, 194793/1993, 200849/1993,202137/1993, 202143/1993, 202219/1993, 202237/1993, 202238/1993,202248/1993, 209062/1993, 212771/1993, 212774/1993, 214178/1993,220829/1993, 222121/1993, 222122/1993, 222251/1993, 228995/1993,237930/1993 and 239232/1993, there have been disclosed techniques ofimparting the sufficiently improved melt tension to a propylene polymerand a resin composition containing this polymer by combining apreliminary polymerization catalyst with a preliminary polymerizationmethod. However, in the techniques disclosed in these publications, thepreliminary polymerization operation which is carried out prior to amain polymerization comprises at least 3 steps, and so the operation isintricate. Besides, its reactivity is usually poor, and a chainnon-conjugated diene which might bring about cyclization and acrosslinking reaction during the reaction is inconveniently used.

DISCLOSURE OF THE INVENTION

Under such circumstances, the present invention has been made for thepurpose of providing an olefin copolymer having excellent thermalstability, transparency and uniformity which can optionally control theactivation energy of the fluidization of a melt and in which high-speedmolding is possible to lower a working cost, and a process forefficiently preparing this copolymer.

The present inventors have intensively researched with the intention ofaccomplishing the above-mentioned object, and as a result, it has beenfound that an olefin copolymer comprising a unit derived from an olefinand a unit derived from a diolefin, having a specific weight-averagemolecular weight and a specific content of the unit derived from thediolefin, and having a specific relation between the content of the unitderived from the diolefin and a content of unsaturated groups in amolecular chain as well as an olefin graft copolymer obtained by thegraft polymerization of this copolymer and an olefin has theabove-mentioned preferable characteristics, and it has also been foundthat these copolymers can efficiently be prepared by the use of aspecific polymerization catalyst. Furthermore, it has be found thatsubstantially unsaturated group-free polymers which can be obtained byhydrogenating the olefin copolymer and the olefin graft copolymer havenot only the above-mentioned preferable characteristics but also anexcellent thermal stability. The present invention has been completed onthe basis of such a knowledge.

That is to say, the present invention provides (I) an olefin copolymerwhich comprises a unit derived from an olefin and a unit derived from adiolefin and in which a weight-average molecular weight is in the rangeof 200 to 800,000, the content of the unit derived from the diolefin isin the range of 0.002 to 30 mol%, and a relation between the content ofthe unit derived from the diolefin (DOU mol%) and the total content ofunsaturated groups observed in a molecular chain (TUS mol%) meets theformula

    0.001≦TUS/DOU≦200,

(II) an olefin graft copolymer prepared by the graft polymerization ofthis olefin copolymer and an olefin, (III) a substantially unsaturatedgroup-free olefin polymer prepared by hydrogenating the olefincopolymer, and (IV) a substantially unsaturated group-free olefin graftpolymer prepared by hydrogenating the olefin graft copolymer.

Furthermore, the present invention provides (I) a process for preparingthe above-mentioned olefin copolymer which comprises the step ofcopolymerizing an olefin and a diolefin in the presence of apolymerization catalyst containing, as main components, (A) a transitionmetal compound and (B) a compound capable of reacting with thetransition metal compound of the component (A) or its derivative to forman ionic complex, (II) a process for preparing the above-mentionedolefin graft copolymer which comprises the steps of copolymerizing anolefin and a diolefin in the presence of a polymerization catalystcontaining, as main components, (A) a transition metal compound and (B)a compound capable of reacting with the transition metal compound of thecomponent (A) or its derivative to form an ionic complex, whereby anolefin copolymer is formed, and then further graft-polymerizing thecopolymer and an olefin in the presence of the above-mentionedpolymerization catalyst, (III) a process for preparing theabove-mentioned olefin copolymer which comprises the step ofhydrogenating, in the presence of a hydrogenation catalyst, the olefincopolymer (I) obtained by the above-mentioned process, and (IV) aprocess for preparing the above-mentioned olefin graft copolymer whichcomprises the step of hydrogenating, in the presence of a hydrogenationcatalyst, the olefin graft copolymer (II) obtained by theabove-mentioned process.

BEST MODE FOR CARRYING OUT THE INVENTION

For an olefin copolymer (I) and an olefin graft copolymer (II) of thepresent invention, olefins and diolefins are used as material monomers.As the olefins, there can be used ethylene, α-olefins having 3 to 20carbon atoms, aromatic vinyl compounds and cyclic olefins. Examples ofthe α-olefins having 3 to 20 carbon atoms include propylene, 1-butene,1-pentene, 4-methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene,1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicosene. Furthermore,the aromatic vinyl compounds include styrene and its derivatives (whichhave substituents containing carbon, halogens, silicon and the like),and typical examples of the aromatic vinyl compounds include styrene,alkylstyrenes such as p-methylstyrene, o-methylstyrene, m-methylstyrene,2,4-dimethylstyrene, 2,5-dimethylstyrene, 3,4-dimethylstyrene,3,5-dimethylstyrene and p-t-butylstyrene, halogenated styrenes such asp-chlorostyrene, m-chlorostyrene, o-chlorostyrene, p-bromostyrene,m-bromostyrene, o-bromostyrene, p-fluorostyrene, m-fluorostyrene,o-fluorostyrene and o-methyl-p-fluorostyrene, and vinylbiphenyls such as4-vinylbiphenyl, 3-vinylbiphenyl and 2-vinylbiphenyl. Moreover, thecyclic olefins preferably have 3 to 20 carbon atoms, and typicalexamples of the cyclic olefins include cyclopentene, cyclohexene,norbornene, 1-methylnorbornene, 5-methylnorbornene, 7-methylnorbornene,5,6-dimethylnorbornene, 5,5,6-trimethylnorbornene, 5-ethylnorbornene,5-propylnorbornene, 5-phenylnorbornene and 5-benzylnorbornene.

In the present invention, these olefins may be used singly or in acombination of two or more thereof.

On the other hand, as the diolefins, there can preferably be usedpolyfunctional monomers selected from cyclic diene compounds andcompounds obtained from at least two similar or different kinds ofresidues selected from the group consisting of an α-olefin residue, astyrene residue and a cyclic olefin residue. Examples of suchpolyfunctional monomers include straight-chain or branched acyclic dienecompounds, monocyclic alicyclic diene compounds, polycyclic alicyclicdiene compounds, cycloalkenyl-substituted alkenes, diene compoundshaving aromatic rings, and diene compounds having the α-olefin residueand the styrene residue in one molecule.

Examples of the straight-chain or branched acyclic diene compoundsinclude 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 1,6-octadiene,1,7-octadiene, 1,9-decadiene, 1,11-dodecadiene, 2-methyl-l,4-pentadiene,2-methyl-1,5-hexadiene and 3-ethyl-1,7-octadiene, and examples of themonocyclic alicyclic diene compounds include 1,3-cyclopentadiene,1,4-cyclohexadiene, 1,5-cyclooctadiene, 1,5-cyclododecadiene,1,2-divinylcyclohexane and 1,3-divinylcyclohexane.

Moreover, examples of the polycyclic alicyclic diene compounds includedicyclopentadiene, norbornadiene, tetrahydroindene,methyltetrahydroindene, bicyclo-(2,2,1)-hepta-2,5-diene,5-methyl-2,5-norbornadiene, and norbornenes of alkenyl, alkylidene,cycloalkenyl and cycloalkylidene, for example, 5-methyl-2-norbornene,5-ethylidene-2-norbornene, 5-isopropylidene-2-norbornene,5-vinylnorbornene, 5-butenylnorbornene,5-(4-cyclopentenyl)-2-norbornene, 5-cyclohexylidene-2-norbornene, andcompounds represented by the formulae ##STR1##

Furthermore, examples of the cycloalkenyl-substituted alkenes includeallylcyclohexene, vinylcyclooctene, allylcyclodecene andvinylcyclododecene, and examples of the diene compounds having thearomatic rings include p-divinylbenzene, m-divinylbenzene,o-divinylbenzene, di-(p-vinylphenyl)methane,1,3-bis(p-vinylphenyl)propane and 1,5-bis(p-biphenyl)pentane.

On the other hand, examples of the diene compounds having the α-olefinresidue and the styrene residue in one molecule includep-(2-propenyl)styrene, m-(2-propenyl)styrene, p-(3-butenyl)styrene,m-(3-butenyl)styrene, o-(3-butenyl)styrene, p-(4-pentenyl)styrene,m-(4-pentyl)styrene, o-(4-pentenyl)styrene, p-(7-octenyl)styrene,p-(1-methyl-3-butenyl)styrene, p-(2-methyl-3-butenyl)styrene,m-(2-methyl-3-butenyl)styrene, o-(2-methyl-3-butenyl)styrene,p-(3-methyl-3-butenyl)styrene, p-(2-ethyl-4-pentenyl)styrene,p-(3-butenyl)-α-methylstyrene, m-(3-butenyl-α-methylstyrene,o-(3-butenyl)-α-methylstyrene, 4-vinyl-4'-(3-butenyl)biphenyl,4-vinyl-3'-(3-butenyl)biphenyl, 4-vinyl-4'-(4-pentenyl)biphenyl,4-vinyl-2'-(4-pentenyl)biphenyl and4-vinyl-4'-(2-methyl-3-butenyl)biphenyl.

These diolefins may be used singly or in a combination of two or morethereof.

In the preparation of the olefin copolymer (I) and the olefin graftcopolymer (II) of the present invention, it is preferable to use apolymerization catalyst containing, as main components, (A) a transitionmetal compound and (B) a compound capable of reacting with thetransition metal compound of the component (A) or its derivative to forman ionic complex.

As the transition metal compound of the component (A), there can be useda transition metal compound containing a metal in the groups III to X ofthe periodic table or a metal of a lanthanide series. Typical preferableexamples of the transition metal include titanium, zirconium, hafnium,chromium, manganese, nickel, palladium and platinum, and particularlypreferable are zirconium, hafnium, titanium, nickel and palladium.

Such a transition metal compound includes various kinds of compounds,but in particular, compounds containing transition metals in the groupsIV and VIII to X, above all, compounds containing transition metalsselected from the group IV of the periodic table, i.e., titanium,zirconium and hafnium can be suitably used. Particularly suitable arecompounds represented by the general formulae

    CpM.sup.1 R.sup.1.sub.a R.sup.2.sub.b R.sup.3.sub.c        (I)

    Cp.sub.2 M.sup.1 R.sup.1.sub.a R.sup.2.sub.b               (II)

    (Cp-A.sub.e -Cp)M.sup.1 R.sup.1.sub.a R.sup.2.sub.b        (III)

or the general formula

    M.sup.1 R.sup.1.sub.a R.sup.2.sub.b R.sup.3.sub.c R.sup.4.sub.d(IV)

and their derivatives.

In the above-mentioned general formulae (I) to (IV), M¹ represents atransition metal such as titanium, zirconium or hafnium in the group Ivof the periodic table, and Cp represents a cyclic unsaturatedhydrocarbon group or a chain unsaturated hydrocarbon group such as acyclopentadienyl group, a substituted cyclopentadienyl group, an indenylgroup, a substituted indenyl group, a tetrahydroindenyl group, asubstituted tetrahydroindenyl group, a fluorenyl group or a substitutedfluorenyl group. R¹, R², R³ and R⁴ each independently represents aσ-bond ligand, a chelate ligand or a ligand such as a Lewis base, andtypical examples of the σ-bond ligand include a hydrogen atom, an oxygenatom, a halogen atom, an alkyl group having 1 to 20 carbon atoms, analkoxy group having 1 to 20 carbon atoms, an aryl group, an alkylarylgroup or an arylalkyl group having 6 to 20 carbon atoms, an acyloxygroup having 1 to 20 carbon atoms, an allyl group, a substituted allylgroup, and a substituent containing a silicon atom. In addition,examples of the chelate ligand include an acetylacetonato group and asubstituted acetylacetonato group. A represents a crosslinkage by acovalent bond. a, b, c and d each is independently an integer of 0 to 4,and e is an integer of 0 to 6. Two or more of R¹, R², R³ and R⁴ may bondto each other to form a ring. In the case that the above-mentioned Cphas a substituent, this substituent is preferably an alkyl group having1 to 20 carbon atoms. In the formulae (II) and (III), the two Cps may bethe same or different from each other.

Examples of the substituted cyclopentadienyl group in theabove-mentioned formulae (I) to (III) include a methylcyclopentadienylgroup, an ethylcyclopentadienyl group, an isopropylcyclopentadienylgroup, a 1,2-dimethylcyclopentadienyl group, atetramethylcyclopentadienyl group, a 1,3-dimethylcyclopentadienyl group,a 1,2,3-trimethylcyclopentadienyl group, a1,2,4-trimethylcyclopentadienyl group, a pentamethylcyclopentadienylgroup and a trimethylsilylcyclopentadienyl group. Furthermore, typicalexamples of R¹ to R⁴ in the above-mentioned formulae (I) to (IV) includea fluorine atom, a chlorine atom, a bromine atom and an iodine atom asthe halogen atoms; a methyl group, an ethyl group, an n-propyl group, anisopropyl group, an n-butyl group, an octyl group and a 2-ethylhexylgroup as the alkyl groups having 1 to 20 carbon atoms; a methoxy group,an ethoxy group, a propoxy group, a butoxy group and a phenoxy group asthe alkoxy groups having 1 to 20 carbon atoms; a phenyl group, a tolylgroup, a xylyl group and a benzyl group as the aryl groups, thealkylaryl groups or the arylalkyl groups having 6 to 20 carbon atoms; aheptadecylcarbonyloxy group as the acyloxy group having 1 to 20 carbonatoms; a trimethylsilyl group and a (trimethylsilyl)methyl group as thesubstituent containing a silicon atom; and ethers such as dimethylether, diethyl ether and tetrahydrofuran, a thioether such astetrahydrothiophene, an ester such as ethyl benzoate, nitriles such asacetonitrile and benzonitrile, amines such as trimethylamine,triethylamine, tributylamine, N,N-dimethylaniline, pyridine,2,2'-bipyridine and phenanthroline, phosphines such as triethylphosphineand triphenylphosphine, chain unsaturated hydrocarbons such as ethylene,butadiene, 1-pentene, isoprene, pentadiene, 1-hexene and theirderivatives, and cyclic unsaturated hydrocarbons such as benzene,toluene, xylene, cycloheptatriene, cyclooctadiene, cyclooctatriene,cyclooctatetraene and their derivatives as the Lewis base. In addition,examples of the crosslinkage by the covalent bond of A in the formula(III) include a methylene crosslinkage, a dimethylmethylenecrosslinkage, an ethylene crosslinkage, a 1,1'-cyclohexylenecrosslinkage, a dimethylsilylene crosslinkage, a dimethylgermilenecrosslinkage and a dimethylstanilene crosslinkage.

Examples of the compound represented by the general formula (I) include(pentamethylcyclopentadienyl)trimethylzirconium,(pentamethylcyclopentadienyl)triphenylzirconium,(pentamethylcyclopentadienyl)tribenzylzirconium,(pentamethylcyclopentadienyl)trichlorozirconium,(pentamethylcyclopentadienyl)trimethoxyzirconium,(cyclopentadienyl)trimethylzirconium,(cyclopentadienyl)triphenylzirconium,(cyclopentadienyl)tribenzylzirconium,(cyclopentadienyl)trichlorozirconium,(cyclopentadienyl)trimethoxyzirconium,(cyclopentadienyl)dimethyl(methoxy)zirconium,(methylcyclopentadienyl)trimethylzirconium,(methylcyclopentadienyl)triphenylzirconium,(methylcyclopentadienyl)tribenzylzirconium,(methylcyclopentadienyl)trichlorozirconium,(methylcyclopentadienyl)dimethyl(methoxy)zirconium,(dimethylcyclopentadienyl)trichlorozirconium,(trimethylcyclopentadienyl)trichlorozirconium,(trimethylcyclopentadienyl)trimethylzirconium,(tetramethylcyclopentadienyl)trichlorozirconium, and these compounds inwhich zirconium is replaced with titanium or hafnium.

Examples of the compound represented by the general formulae (II)include bis(cyclopentadienyl)dimethylzirconium,bis(cyclopentadienyl)diphenylzirconium,bis(cyclopentadienyl)diethylzirconium,bis(cyclopentadienyl)dibenzylzirconium,bis(cyclopentadienyl)dimethoxyzirconium,bis(cyclopentadienyl)dichlorozirconium,bis(cyclopentadienyl)dihydridozirconium,bis(cyclopentadienyl)monochloromonohydridozirconium,bis(methylcyclopentadienyl)dimethylzirconium,bis(methylcyclopentadienyl)dichlorozirconium,bis(methylcyclopentadienyl)dibenzylzirconium,bis(pentamethylcyclopentadienyl)dimethylzirconium,bis(pentamethylcyclopentadienyl)dichlorozirconium,bis(pentamethylcyclopentadienyl)dibenzylzirconium,bis(pentamethylcyclopentadienyl)chloromethylzirconium,bis(pentamethylcyclopentadienyl) hydridomethylzirconium,(cyclopentadienyl)(pentamethylcyclopentadienyl)dichlorozirconium, andthese compounds in which zirconium is replaced with titanium or hafnium.

Furthermore, examples of the compound represented by the general formula(III) include ethylenebis(indenyl)dimethylzirconium,ethylenebis(indenyl)dichlorozirconium,ethylenebis(tetrahydroindenyl)dimethylzirconium,ethylenebis(tetrahydroindenyl)dichlorozirconium,dimethylsilylenebis(cyloropentadienyl)dimethylzirconium,dimethylsilylenebis(cyloropentadienyl)dichlorozirconium,isopropylidene(cyloropentadienyl)(9-fluorenyl)dimethylzirconium,isopropylidene(cyloropentadienyl)(9-fluorenyl)dichlorozirconium,[phenyl(methyl)methylene](9-fluorenyl)(cycylopentadienyl)dimethylzirconium,diphenylmethylene(cyclopentadienyl)(9-fluorenyl)dimethylzirconium,ethylene(-9fluorenyl)(cyclopentadienyl)dimethylzirconium,cyclohexalidene(9-fluorenyl)(cyclopentadienyl)dimethylzirconium,cyclopentylidene(9-fluorenyl)(cyclopentadienyl)dimethylzirconium,cyclobutylidene(9-fluorenyl)(cyclopentadienyl)dimethylzirconium,dimethylsilylene(9-fluorenyl)(cyclopentadienyl)dimethylzirconium,dimethylsilylenebis(2,3,5-trimethylcyclopentadienyl)dichlorozirconium,dimethylsilylenebis(2,3,5-trimethylcyclopentadienyl)dimethylzirconium,dimethylsilylenebis(indenyl)dichlorozirconium, and these compounds inwhich zirconium is replaced with titanium or hafnium.

Moreover, examples of the compound represented by the general formula(IV) include tetramethylzirconium, tetrabenzylzirconium,tetramethoxyzirconium, tetraethoxyzirconium, tetrabutoxyzirconium,tetrachlorozirconium, tetrabromozirconium, butoxytrichlorozirconium,dibutoxydichlorozirconium, bis(2,5-di-t-butylphenoxy)dimethylzirconium,bis(2,5-di-t-butylphenoxy)dichlorozirconium, zirconiumbis(acetylacetonato), and these compounds in which zirconium is replacedwith titanium or hafnium.

Furthermore, as the component (A), there can suitably be used a group IVtransition compound having, as the ligand, a multiple ligand compound inwhich in the above-mentioned general formula (III), two substituted orunsubstituted conjugated cyclopentadienyl groups (however, at least oneof which is a substituted cyclopentadienyl group) is bonded to eachother via an element selected from the group XIV of the periodic table.

An example of such a compound is a compound represented by the generalformula (V) ##STR2## or its derivative.

In the above-mentioned general formula (V), Y¹ represents a carbon atom,a silicon atom, a germanium atom or a tin atom, R⁵ _(t) --C₅ H_(4-t) andR⁵ _(u) --C₅ H_(4-u) each represents a substituted cyclopentadienylgroup, and t and u each are an integer of 1 to 4. Here, R⁵ s eachrepresents a hydrogen atom, a silyl group or a hydrocarbon group, andthey may be the same or different from each other. In at least either ofthe cyclopentadienyl groups, R⁵ is present on at least either of carbonatoms adjacent to the carbon atom bonded to Y¹. R⁶ represents a hydrogenatom, an alkyl group having 1 to 20 carbon atoms, or an aryl group, analkylaryl group or an arylalkyl group having 6 to 20 carbon atoms. M²represents a titanium atom, a zirconium atom or a hafnium atom, X¹represents a hydrogen atom, a halogen atom, an alkyl group having 1 to20 carbon atoms, an aryl group, an alkylaryl group or an arylalkyl grouphaving 6 to 20 carbon atoms, or an alkoxy group having 1 to 20 carbonatoms. X¹ may be the same or different from each other, and similarly,R⁶ is may be the same or different from each other.

Moreover, examples of the substituted cyclopentadienyl group in thegeneral formula (V) include a methylcyclopentadienyl group, anethylcyclopentadienyl group, an isopropylcyclopentadienyl group, a1,2-dimethylcyclopentadienyl group, a 1,3-dimethylcyclopentadienylgroup, a 1,2,3-trimethylcyclopentadienyl group and a1,2,4-trimethylcyclopentadienyl group. Typical examples of X¹ include F,Cl, Br and I as the halogen atoms; a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an octyl group anda 2-ethylhexyl group as the alkyl group having 1 to 20 carbon atoms; amethoxy group, an ethoxy group, a propoxy group, a butoxy group and aphenoxy group as the alkoxy groups having 1 to 20 carbon atoms; and aphenyl group, a tolyl group, a xylyl group and a benzyl group as thearyl group, the alkylaryl group or the arylalkyl group having 6 to 20carbon atoms. Typical examples of the R⁶ include a methyl group, anethyl group, a phenyl group, a tolyl group, a xylyl group and a benzylgroup.

Examples of the compound having the general formula (V) includedimethylsilylenebis(2,3,5-trimethylcyclopentadienyl)zirconium dichlorideand this compound in which zirconium is replaced with titanium orhafnium.

In addition, the compound having the general formula (V) also includescompounds represented by the general formula (VI): ##STR3## In thecompound of the general formula (VI), Cp represents a cyclic unsaturatedhydrocarbon group or a chain unsaturated hydrocarbon group such as acyclopentadienyl group, a substituted cyclopentadienyl group, an indenylgroup, a substituted indenyl group, a tetrahydroindenyl group, asubstituted tetrahydroindenyl group, a fluorenyl group or a substitutedfluorenyl group. M³ represents a titanium atom, a zirconium atom or ahafnium atom, X² represents a hydrogen atom, a halogen atom, an alkylgroup having 1 to 20 carbon atoms, an aryl group, an alkylaryl group oran arylalkyl group having 6 to 20 carbon atoms, or an alkoxy grouphaving 1 to 20 carbon atoms. Z represents SIR⁷ ₂, CR⁷ ₂, SiR⁷ ₂ SiR⁷ ₂,CR⁷ ₂ CR⁷², CR⁷ ₂ CR⁷ ₂ CR⁷ ₂, CR⁷ ═CR⁷, CR⁷ ₂ SiR⁷ ₂ or GeR⁷ ₂, and Y²represents --N(R⁸)--, --O--, --S-- or --P(R⁸)--. The above-mentioned R⁷is a group selected from the group consisting of a hydrogen atom, analkyl group having 20 or less non-hydrogen atoms, an aryl group, a silylgroup, a halogenated alkyl group, a halogenated aryl group and acombination thereof, and R⁸ is an alkyl group having 1 to 10 carbonatoms or an aryl group having 6 to 10 carbon atoms, or R⁸ may form acondensed ring of one or more R⁷ s and 30 or less non-hydrogen atoms.Moreover, w represents 1 or 2.

Typical examples of the compound represented by the general formula (VI)include (tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediylzirconium dichloride,(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyltitanium dichloride,(methylamido)(tetramethyl-η⁵ -cyclopentadienyl)-1,2-ethanediylzirconiumdichloride, (methylamido) (tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyltitanium dichloride,(ethylamido)(tetramethyl-η⁵ -cyclopentadienyl)-methylenetitaniumdichloride, (tert-butylamido)dimethyl(tetramethyl-η⁵-cyclopentadienyl)silanetitanium dichloride,(tert-butylamido)dimethyl-(tetramethyl-η⁵-cyclopentadienyl)silanezirconium dibenzyl,(benzylamido)dimethyl(tetramethyl-η⁵ -cyclopentadienyl)silanetitaniumdichloride and (phenylphosphide)dimethyl-(tetramethyl-η⁵-cyclopentadienyl)silanezirconium dibenzyl.

No particular restriction is put on transition metal compoundscontaining transition metals in the groups V to X, and typical examplesof the chromium compound include tetramethylchromium,tetra(t-butoxy)chromium, bis(cyclopentadienyl)chromium,hydridotricarbonyl(cyclopentadienyl)chromium,hexacarbonyl(cyclopentadienyl)chromium, bis(benzene)chromium,tricarbonyltris(triphenyl phosphonate)chromium, tris(allyl)chromium,triphenyltris(tetrahydrofuran)chromium and chromiumtris(acetyl-acetonato).

Typical examples of the manganese compounds includetricarbonyl(cyclopentadienyl)manganese, pentacarbonylmethylmanganese,bis(cyclopentadienyl)manganese and manganese bis(acetylacetonato).

Typical examples of the nickel compound includedicarbonylbis(triphenylphosphine)nickel,dibromobis(triphenylphosphine)nickel,dinitrogenbis[bis(tricyclohexylphosphine)nickel],chlorohydridobis(tricyclohexylphosphine)nickel,chloro(phenyl)bis(triphenylphosphine)nickel,dimethylbis(trimethylphosphine)nickel, diethyl(2,2'-bipyridyl)nickel,bis(allyl)nickel, bis(cyclopentadienyl)nickel,bis(methylcyclopentadienyl)nickel,bis(pentamethyl-cyclopentadienyl)nickel, allyl(cyclopentadienyl)nickel,(cyclopentadienyl)(cyclooctadiene)nickel tetrafluoroborate,bis(cyclooctadiene)nickel, nickel bisacetylacetonato, allylnickelchloride, tetrakis(triphenylphosphine)nickel, nickel chloride, andcompounds represented by the formulae (C₆ H₅)Ni[OC(C₆ H₅)CH═p(C₆ H₅)₂][p(C₆ H₅)₃ ] and (C₆ H₅)Ni[OC(C₆ H₅)C(SO₃ Na)═P(C₆ H₅)₂ ][P(C₆ H₅)₃ ].

Typical examples of the palladium compound includedichlorobis(benzonitrile)Palladium,carbonyltris(triphenylphosphine)palladium,dichlorobis(triethylphosphine)palladium,bis(isocyanated-t-butyl)palladium, palladium bis-(acetylacetonato),dichloro(tetraphenylcyclobutadiene)palladium,dichloro(1,5-cyclooctadiene)palladium, allyl(cyclopentadienyl)palladium,bis(allyl)palladium, allyl(1,5-cyclooctadiene)palladiumtetrafluoroborate, (acetylacetonato)(1,5-cyclooctadiene)palladiumtetrafluoroborate and tetrakis(acetonitrile) palladiumtetrafluoroborate.

In the polymerization catalyst which is used in the present invention,the transition metal compounds of the component (A) may be used singlyor in a combination of two or more thereof.

On the other hand, in the polymerization catalyst, as the component (B),there is used the compound capable of reacting with the above-mentionedtransition metal compound or its derivative to form an ionic complex.Examples of this compound (B) include (B-1) an ionic compound capable ofreacting with the transition metal compound of the component (A) to forman ionic complex, (B-2) an aluminoxane and (B-3) a Lewis acid.

As the component (B-1), any compound can be used, so long as it canreact with the transition metal compound of the component (A) to form anionic complex, but compounds represented by the following generalformulae (VII) and (VIII) can suitably be used:

    ([L.sup.1 -R.sup.9 ].sup.k+).sub.p ([Z].sup.-).sub.q       (VII)

    ([L.sup.2 ].sup.k+).sub.p ([Z].sup.-).sub.q                (VIII)

(wherein L² is M⁵ , R¹⁰ R¹¹ M⁶, R¹² ₃ C or R¹³ M⁶). [in the formulae(VII) and (VIII), L¹ is a Lewis base, [Z]⁻ is a non-ligand anion [Z¹ ]⁻⁻or [Z² ]⁻, and here [Z¹ ]⁻ is an anion in which a plurality of groupsare bonded to an element, i.e., [M⁴ A¹ A² . . . A^(n) ]⁻ (wherein M⁴ isan element in the groups V to XV of the periodic table, preferably anelement in the groups XIII to XV. A¹ -A^(n) are each a hydrogen atom, ahalogen atom, an alkyl group having 1 to 20 carbon atoms, a dialkylaminogroup having 2 to 40 carbon atoms, an alkoxy group having 1 to 20 carbonatoms, an aryl group having 6 to 20 carbon atoms, an aryloxy grouphaving 6 to 20 carbon atoms, an alkylaryl group having 7 to 40 carbonatoms, an arylalkyl group having 7 to 40 carbon atoms, ahalogen-substituted hydrocarbon group having 1 to 20 carbon atoms, anacyloxy group having 1 to 20 carbon atoms, an organic metalloid group,or a heteroatom-containing hydrocarbon group having 2 to 20 carbonatoms. Two or more of A¹ -A^(n) may form a ring. n is an integer of [(avalence of the central metal M⁴)+1]), and [Z² ]⁻ represents a Brφnstedacid alone in which a logarithm (pKa) of a reciprocal number of an aciddissociation constant is -10 or less, a conjugate base of a combinationof the Brφnsted acid and a Lewis acid, or a conjugate base which isusually defined as an ultra-strong acid. The group [Z² ]⁻ may becoordinated by a Lewis base. Furthermore, R⁹ represents a hydrogen atom,an alkyl group having 1 to 20 carbon atoms, or an aryl group, analkylaryl group or an arylalkyl group having 6 to 20 carbon atoms, andR¹⁰ and R¹¹ each represents a cyclopentadienyl group, a substitutedcyclopentadienyl group, an indenyl group or a fluorenyl group, and R¹²represents an alkyl group, an aryl group, an alkylaryl group or anarylalkyl group having 1 to 20 carbon atoms. R¹³ represents a largecyclic ligand such as tetraphenylporphyrin or phthalocyanine. k is anion valence of [L¹ -R⁹ ] or [L² ] and it is an integer of 1 to 3, and pis an integer of 1 or more, and q=(k×p). M⁵ contains an element in thegroups I to III, XI to XIII and XVII of the periodic table, and M⁶represents an element in the groups VII to XII].

Here, typical examples of L¹ include ammonia, amines such asmethylamine, aniline, dimethylamine, diethylamine, N-methylaniline,diphenylamine, N,N-dimethylaniline, trimethylamine, triethylamine,tri-n-butylamine, methyldiphenylamine, pyridine,p-bromo-N,N-dimethylaniline and p-nitro-N,N-dimethylaniline, phosphinessuch as triethylphosphine, triphenylphosphine and diphenylphosphine, athioether such as tetrahydrothiophene, an ester such as ethyl benzoate,and nitriles such as acetonitrile and benzonitrile.

Typical examples of R⁹ include hydrogen, a methyl group, an ethyl group,a benzyl group and a trityl group, and typical examples of R¹⁰ and R¹¹include a cyclopentadienyl group, a methylcyclopentadienyl group, anethylcyclopentadienyl group and a pentamethylcyclopentadienyl group.Typical examples of R¹² include a phenyl group, a p-tolyl group and ap-methoxyphenyl group, and typical examples of R¹³ include atetraphenylporphine, phthalocyanine, allyl and methallyl. Moreover,typical examples of M⁵ include Li, Na, K, Ag, Cu, Br, I and I₃, andtypical examples of M⁶ include Mn, Fe, Co, Ni and Zn.

Furthermore, in [Z¹ ]⁻, i.e., [M⁴ A¹ A² . . . A^(n) ]⁻, typical examplesof M⁴ include B, Al, Si, P, As and Sb, and B and Al are preferable.Moreover, typical examples of A¹, A² -A^(n) include a dimethylaminogroup and a diethylamino group as the dialkylamino group; a methoxygroup, an ethoxy group, an n-butoxy group and a phenoxy group as thealkoxy group or the aryloxy group; a methyl group, an ethyl group, ann-propyl group, an isopropyl group, an n-butyl group, an isobutyl group,an n-octyl group, an n-eicosyl group, a phenyl group, a p-tolyl, abenzyl group, a 4-t-butylphenyl group and a 3,5-dimethylphenyl group asthe hydrocarbon group; fluorine, chlorine, bromine and iodine as thehalogen atoms; a p-fluorophenyl group, a 3,5-difluorophenyl group, apentachlorophenyl group, a 3,4,5-trifluorophenyl group, apentafluorophenyl group, a 3,5-bis(trifluoromethyl)phenyl group and abis(trimethylsilyl)methyl group as the heteroatom-containing hydrocarbongroup; and a pentamethylantimony group, a trimethylsilyl group, atrimethylgermil group, a diphenylarsine group and a dicyclohexylantimonygroup as the organic metalloid group.

Furthermore, typical examples of the non-ligand anion, i.e., theBrφnsted acid alone in which the pKa is -10 or less, or the conjugatebase [Z² ]⁻ of the combination of the Brφnsted acid and the Lewis acidinclude a trifluoromethanesulfonic acid anion (CF₃ SO₃)⁻, abis(trifluoromethanesulfonyl)methyl anion, abis(trifluoromethanesulfonyl)benzyl anion, abis(trifluoromethanesulfonyl)amide, a perchloric acid anion (ClO₄)⁻, atrifluoroacetic acid anion (CF₃ CO₂)⁻, a hexafluoroantimony anion(SbF₆)⁻, a fluorosulfonic acid anion (FSO₃)⁻, a chlorosulfonic acidanion (ClSO₃)⁻, a fluorosulfonic acid anion-5-antimony fluoride (FSO₃-SbF₅)⁻, a fluorosulfonic acid anion-5-arsenic fluoride (FSO₃ -AsF₅)⁻and a trifluoromethanesulfonic acid-5-antimony fluoride (CF₃ SO₃-SbF₅)⁻.

Typical examples of the ionic compound capable of reacting with thetransition metal compound of the above-mentioned component (A) to forman ionic complex, i.e., the (B-1) component compound includetriethylammonium tetraphenylborate, tri-n-butylammoniumtetraphenylborate, trimethylammonium tetraphenylborate,tetraethylammonium tetraphenylborate, methyl(tri-n-butyl)ammoniumtetraphenylborate, benzyl(tri-n-butyl)ammonium tetraphenylborate,dimethyldiphenylammonium tetraphenylborate, triphenyl(methyl)ammoniumtetraphenylborate, trimethylanilinium tetraphenylborate,methylpyridinium tetraphenylborate, benzylpyridinium tetraphenylborate,methyl(2-cyanopyridinium) tetraphenylborate, triethylammoniumtetrakis(pentafluorophenyl)borate, tri-n-butylammoniumtetrakis(pentafluorophenyl)borate, triphenylammoniumtetrakis(pentafluorophenyl)borate, tetra-n-butylammoniumtetrakis(pentafluorophenyl)borate, tetraethylammoniumtetrakis(pentafluorophenyl)borate, benzyl(tri-n-butyl)ammoniumtetrakis(pentafluorophenyl)borate, methyldiphenylammoniumtetrakis(pentafluorophenyl)borate, triphenyl(methyl)ammoniumtetrakis(pentafluorophenyl)borate, methylaniliniumtetrakis(pentafluorophenyl)borate, dimethylaniliniumtetrakis(pentafluorophenyl)borate, trimethylaniliniumtetrakis(pentafluorophenyl)borate, methylpyridiniumtetrakis(pentafluorophenyl)borate, benzylpyridiniumtetrakis(pentafluorophenyl)borate, methyl(2-cyanopyridinium)tetrakis(pentafluorophenyl)borate, benzyl(2-cyanopyridinium)tetrakis(pentafluorophenyl)borate, methyl(4-cyanopyridinium)tetrakis(pentafluorophenyl)borate, triphenylphosphoniumtetrakis(pentafluorophenyl)borate, dimethylaniliniumtetrakis[bis(3,5-ditrifluoromethyl)phenyl]borate, ferroceniumtetraphenylborate, silver tetraphenylborate, trityl tetraphenylborate,tetraphenylporphyrinmanganese tetraphenylborate, ferroceniumtetrakis(pentafluorophenyl)borate, (1,1'-dimethylferrocenium)tetrakis(pentafluorophenyl)borate, decamethylferroceniumtetrakis(pentafluorophenyl)borate, silvertetrakis(pentafluorophenyl)borate, trityltetrakis(pentafluorophenyl)borate, lithiumtetrakis(pentafluorophenyl)borate, sodiumtetrakis(pentafluorophenyl)borate, tetraphenylporphyrinmanganesetetrakis(pentafluorophenyl)borate, silver tetrafluoroborate, silverhexafluorophosphate, silver hexafluoroarsenate, silver perchlorinate,silver trifluoroacetate and silver trifluoromethanesulfonate.

The ionic compounds, which are the (B-1) components, capable of reactingwith the transition metal compound of the above-mentioned component (A)to form an ionic complex may be used singly or in a combination of twoor more thereof.

On the other hand, as the aluminoxane of the (B-2) component, there canbe mentioned a chain aluminoxane represented by the general formula (IX)##STR4## (wherein R¹⁴ s each represents a halogen atom, or an alkylgroup, an alkenyl group, an aryl group or an arylalkyl group having 1 to20 carbon atoms, preferably 1 to 12 carbon atoms, the respective R¹⁴ smay be the same or different, s represents a polymerization degree, andit is an integer of usually 3 to 50, preferably 7 to 40) and a cyclicaluminoxane represented by the general formula (X) ##STR5## (wherein R¹⁴s and s are as defined above).

Among the compounds of the general formulae (IX) and (X), thealuminoxanes having a polymerization degree of 7 or more are preferable.In the case that the aluminoxane having a polymerization degree of 7 ormore, or a mixture of these aluminoxanes is used, a high activation canbe obtained. Furthermore, modified aluminoxanes can also suitably beused which can be obtained by modifying the aluminoxanes represented bythe general formulae (IX) and (X) with a compound such as water havingan active hydrogen and which are insoluble in usual solvents.

As a preparation method of the above-mentioned aluminoxanes, a methodcan be mentioned in which an alkylaluminum is brought into contact witha condensation agent such as water, but no particular restriction is puton its means, and the reaction can be carried out in a known manner. Forexample, there are (1) a method which comprises dissolving an organicaluminum compound in an organic solvent, and then bringing the solutioninto contact with water, (2) a method which comprises first adding anorganic aluminum compound at the time of polymerization, and then addingwater, (3) a method which comprises reacting water of crystallizationcontained in a metallic salt or water adsorbed by an inorganic substanceor an organic substance with an organic aluminum compound, and (4) amethod which comprises reacting a tetraalkyldialuminoxane with atrialkylaluminum, and further reacting with water. In this connection,the aluminoxane may be that which is insoluble in toluene.

These aluminoxanes may be used singly or in a combination of two or morethereof.

Furthermore, no particular restriction is put on the Lewis acid which isthe (B-3) component, and this Lewis acid may be an organic compound or asolid inorganic compound. As the organic compound, boron compounds andaluminum compounds are preferably used, and as the inorganic compound,magnesium compounds and aluminum compounds are preferably used. Examplesof the aluminum compounds includebis(2,6-di-t-butyl-4-methylphenoxy)aluminum methyl and(1,1-bi-2-naphthoxy)aluminum methyl, examples of the magnesium compoundsinclude magnesium chloride and diethoxymagnesium, examples of thealuminum compounds include aluminum oxide and aluminum chloride, andexamples of the boron compounds include triphenylboron,tris(pentafluorophenyl)boron, tris[3,5-bis(trifluoromethyl)phenyl]boron,tris[(4-fluoromethyl)phenyl]boron, trimethylboron, triethylboron,tri-n-butylboron, tris(fluoromethyl)boron, tris(pentafluoroethyl)boron,tris(nonafluorobutyl)boron, tris(2,4,6-trifluorophenyl)boron,tris(3,5-difluoro)boron, tris[3,5-bis(trifluoromethyl)phenyl]boron,bis(pentafluorophenyl)fluoroboron, diphenylfluoroboron,bis(pentafluorophenyl)chloroboron, dimethylfluoroboron,diethylfluoroboron, di-n-butylfluoroboron,pentafluorophenyldifluoroboron, phenyldifluoroboron,pentafluorophenyldichloroboron, methyldifluoroboron, ethyldifluoroboron,n-butyldifluoroboron and boron trifluoride.

These Lewis acids may be used singly or in a combination of two or morethereof.

The use ratio of the catalyst component (A) to the catalyst component(B) in the polymerization catalyst which can be used in the presentinvention is preferably in the range of 10:1 to 1:100, more preferably2:1 to 1:10, most preferably 1:1 to 1:5 in terms of a molar ratio in thecase that the compound (B-1) is used as the catalyst component (B), andit is preferably in the range of 1:20 to 1:10000, more preferably 1:100to 1:2000 in terms of a molar ratio in the case that the compound (B-2)is used. Moreover, the ratio is preferably in the range of 10:1 to1:2000, more preferably 5:1 to 1:1000, most preferably 2:1 to 1:500 interms of a molar ratio in the case that the compound (B-3) is used.

The polymerization catalyst may contain the abovementioned component (A)and component (B) as the main components, or it may contain thecomponent (A), the component (B) and the organic aluminum compound (C)as the main components.

Here, as the organic aluminum compound which is the component (C), therecan be used a compound represented by the general formula (XI)

    R.sup.15.sub.r AlQ.sub.3-r                                 (XI)

(wherein R¹⁵ represents an alkyl group having 1 to 10 carbon atoms, Q isa hydrogen atom, an alkoxy group having 1 to 20 carbon atoms, an arylgroup having 6 to 20 carbon atoms or a halogen atom, and r is an integerof 1 to 3).

Typical examples of the compound represented by the general formula (XI)include trimethylaluminum, triethylaluminum triisopropylaluminum,triisobutylaluminum, dimethylaluminum chloride, diethylaluminumchloride, methylaluminum dichloride, ethylaluminum dichloride,dimethylaluminum fluoride, diisobutylaluminum hydride, diethylaluminumhydride and ethylaluminum sesquichloride.

These organic aluminum compounds may be used singly or in a combinationof two or more thereof.

The use ratio of the catalyst component (A) to the catalyst component(C) is preferably in the range of 1:1 to 1:2000, more preferably 1:5 to1:1000, most preferably 1:10 to 1:500 in terms of a molar ratio. By theuse of the catalyst component (C), a polymerization activity pertransition metal can be improved, but if its amount is too large, theorganic aluminum compound is wasteful and it remains in large quantitiesin a polymer unpreferably.

In the present invention, at least one of the catalyst components can besupported on a suitable carrier and then used. No particular restrictionis put on the kind of carrier, and inorganic oxide carriers, otherinorganic carriers and organic carriers all can be used, but theinorganic oxide carriers and the other inorganic carriers areparticularly preferable.

Typical examples of the inorganic oxide carriers include SiO₂, Al₂ O₃,MgO, ZrO₂, TiO₂, Fe₂ O₃, B₂ O₃, CaO, ZnO, BaO, ThO₂ and mixturesthereof, for example, silica-alumina, zeolite, ferrite, sepiolite andglass fiber. Above all, SiO₂ and Al₂ O₃ are particularly preferable. Inthis connection, the above-mentioned inorganic oxide carrier may containa small amount of a carbonate, a nitrate, a sulfate or the like.

On the other hand, examples of the carriers other than mentioned aboveinclude magnesium compounds and their complex salts represented by thegeneral formula MgR¹⁶ _(x) X³ _(y) which are typified by magnesiumcompounds such as MgCl₂ and Mg(OC₂ H₅)₂. Here, R¹⁶ represents an alkylgroup having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbonatoms or an aryl group having 6 to 20 carbon atoms, X³ is a halogen atomor an alkyl group having 1 to 20 carbon atoms, x is from 0 to 2, y isfrom 0 to 2, and x+y=2. The respective R¹⁶ s and X³ s may be the same ordifferent.

Furthermore, examples of the organic carriers include polymers such aspolystyrene, substituted polystyrenes, styrene-divinylbenzene copolymer,polyethylene, polypropylene and polyarylate, starch and carbon.

As the carriers which can be used in the present invention, preferableare MgCl₂, MgCl(OC₂ H₅), Mg(OC₂ H₅)₂, SiO₂, Al₂ O₃ and the like. Thestate of the carrier depends upon its kind and a manufacturing process,but its average particle diameter is usually in the range of 1 to 300μm, preferably 10 to 200 μm, more preferably 20 to 100 μm.

If the particle diameter is small, the fine power of the polymerincreases, and if the particle diameter is large, the coarse particlesof the polymer increase, which causes the deterioration of a bulkdensity and the clogging of a hopper.

Moreover, the specific surface area of the carrier is usually in therange of 1 to 1000 m² /g, preferably 50 to 500 m² /g, and its porevolume is usually in the range of 0.1 to 5 cm³ /g, preferably 0.3 to 3cm³ /g.

If either of the specific surface area and the pore volume deviates fromthe above-mentioned range, a catalyst activity deteriorates sometimes.In this connection, the specific surface area and the pore volume can becalculated from the volume of an adsorbed nitrogen gas in accordancewith a BET method [refer to Journal of the American Chemical Society,Vol. 60, p. 309 (1983)].

Furthermore, it is desirable that the above-mentioned carrier, whenused, is calcined usually at 150 to 1000° C., preferably 200° to 800° C.

In the case that at least one of the catalyst components is supported onthe above-mentioned carrier, it is desirable that at least one of thecatalyst component (A) and the catalyst component (B), preferably bothof the catalyst component (A) and the catalyst component (B) aresupported.

No particular restriction is put on a method for supporting at least oneof the component (A) and the component (B), but there can be employed,for example, (1) a method of mixing at least one of the component (A)and the component (B) with the carrier, (2) a method of mixing, in aninert solvent, at least one of the component (A) and the component (B)with the carrier, after the carrier has been treated with an organicaluminum compound or a halogen-containing silicon compound, (3) a methodof reacting the carrier, the component (A) and/or the component (B) withthe organic aluminum compound or the halogen-containing siliconcompound, (4) a method of mixing the component (B) or the component (A)with the carrier, after the component (A) or the component (B) has beensupported on the carrier, (5) a method of mixing the carrier with acatalytic reaction product of the component (A) and the component (B),and (6) a method in which the carrier is allowed to coexist in thecatalytic reaction of the component (A) with the component (B).

Incidentally, in the reactions of the abovementioned methods (4), (5)and (6), the organic aluminum compound of the component (C) can beadded.

The thus obtained catalyst may be taken out as a solid by oncedistilling off the solvent and then used for the polymerization, or maybe used for the polymerization as it is.

Moreover, in the present invention, the catalyst can be formed bycarrying out the operation of supporting at least one of the component(A) and the component (B) on the carrier in a polymerization system. Forexample, a process can be employed which comprises adding at lease oneof the component (A) and the component (B), the carrier and, ifnecessary, the organic aluminum compound of the above-mentionedcomponent (C), further adding a material monomer under atmosphericpressure to 20 kg/cm², and then doing prepolymerization at -20° to 200°C. for a period of 1 minute to 2 hours to produce catalyst particles.

In the present invention, the use ratio of the above-mentioned compound(B-1) to the carrier is preferably in the range of 1:5 to 1:10000, morepreferably 1:10 to 1:500, and the use ratio of the compound (B-2) to thecarrier is preferably in the range of 1:0.5 to 1:1000, more preferably1:1 to 1:50 in terms of a weight ratio. Furthermore, it is desirablethat the use ratio of the compound (B-3) to the carrier is preferably inthe range of 1:5 to 1:10000, more preferably 1:10 to 1:500 in terms of aweight ratio. In addition, it is desirable that the use ratio of thecomponent (A) to the carrier is preferably in the range of 1:5 to1:10000, more preferably 1:10 to 1:500 in terms of a weight ratio.

If the use ratio of the component (B) [the component (B-1), thecomponent (B-2) or the component (B-3)] to the carrier, or the use ratioof the component (A) to the carrier deviates from the above-mentionedrange, the activity deteriorates sometimes. The average particlediameter of the thus prepared catalyst for the polymerization is usuallyin the range of 2 to 200 μm, preferably 10 to 150 μm, particularlypreferably 20 to 100 μm, and the specific surface area of the catalystis usually in the range of 20 to 1000 m² /g, preferably 50 to 500 m² /g.If the average particle diameter is less than 2 μm, the amount of thefine powder in the polymer increases sometimes, and if it is more than200 μm, the coarse particles in the polymer increase sometimes. If thespecific surface area is less than 20 m² /g, the activity deterioratessometimes, and if it is in excess of 1000 m² /g, the bulk density of thepolymer deteriorates sometimes. Furthermore, in the catalyst, the amountof the transition metal in 100 g of the carrier is usually in the rangeof 0.05 to 10 g, particularly preferably 0.1 to 2 g. If the amount ofthe transition metal is outside the above-mentioned range, the activitydeteriorates sometimes.

By supporting the component on the carrier, there can be obtained thepolymer having a high bulk density and an excellent particle diameterdistribution which are industrially advantageous.

In this connection, when the olefin graft copolymer (II) is prepared, itis desirable that such a polymerization catalyst as not to form anydouble bond at a terminal is selected as the polymerization catalystfrom the above-mentioned polymerization catalysts and then used.

The olefin copolymer (I) of the present invention, even if it is aprecursor of the olefin graft copolymer (II), can be obtained by thereaction step [1], i.e., the step in which the above-mentioned olefin ispolymerized with the diolefin in the presence of the above-mentionedpolymerization catalyst. In this case, the polymerization catalyst issuitably selected from the above-mentioned polymerization catalysts andthen used so as to obtain the olefin copolymer (I) in which a relationbetween the content of a unit derived from the diolefin and the totalcontent of unsaturated groups is specified. In this reaction step [1],by the use of the diolefin, the introduction of a carbon-carbonunsaturated group and a crosslinking reaction are carried out, and areaction of producing an unsaturated group such as a terminal vinylgroup derived from an olefin active terminal is advanced.

With regard to the feed ratio of the olefin to the diolefin, both thecomponents are used so that a diolefin/-olefin molar ratio may beusually within the range of 1/10⁶ to 10² /1, preferably 1/10⁴ to 10/1.Furthermore, one or more kinds of olefins can be used, and itscomposition can be optionally set in consideration of the amount of anunsaturated group such as the required terminal vinyl group and acomposition ratio of the copolymer, but by increasing the feed ratio ofethylene, the amount of the terminal vinyl group can be increased. Inaddition, by the use of titanium, vanadium or a chromium compound as thecatalyst, the amount of the terminal vinyl group can be increased.

The ratio of the monomer component to the catalyst component in thereaction step [1] is selected so that a monomer component/catalystcomponent (A) molar ratio may be in the range of 10⁷ /1 to 10/1,preferably 10⁵ /1 to 10² /1. Moreover, a polymerization pressure isusually selected in the range of from atmospheric pressure to 30kg/cm².G, and a polymerization temperature is preferably on a higherside in the range in which the catalyst activity is not impaired, and itis usually selected in the range of -100° to 300° C., preferably -50° to200° C., more preferably 10° to 180° C.

The thus obtained olefin copolymer (I) of the present invention is along-chain branched copolymer comprising a unit derived from the olefinand a unit derived from the diolefin, and its weight-average molecularweight is required to be in the range of 200 to 800,000, preferably 500to 700,000, more preferably 1,000 to 700,000. Incidentally, even if theweight-average molecular weight of the olefin copolymer (I) of thepresent invention is in the relatively low range of 200 to 100,000, agraft copolymer having a sufficiently high molecular weight can beobtained by the graft polymerization of the olefin. This weight-averagemolecular weight is a molecular weight in terms of polyethylene measuredby gel permeation chromatography (GPC).

It is necessary that the content of the unit derived from the diolefinin the copolymer (I) should be in the range of 0.002 to 30 mol%,preferably 0.004 to 25 mol%, more preferably 0.008 to 15 mol%. If thiscontent is less than 0.002 mol%, the crosslinking reaction and theamount of a pendant unsaturated residue are insufficient, so that agraft efficiency in the undermentioned reaction step [2] is low.Moreover, if the content is more than 30 mol%, the crosslinking reactionexcessively occurs, so that the tendency of nonfusion is observed.

In the olefin copolymer (I), a relation between the content of the unitderived from the diolefin (DOU mol%) and the total content of theunsaturated group (TUS mol%) observed in a molecular chain is requiredto meet the formula

    0.001≦TUS/DOU≦200

preferably

    0.005≦TUS/DOU≦150

more preferably

    0.01≦TUS/DOU≦100.

If the TUS/DOU is less than 0.001, the amount of the unsaturated residuewhich is a substantial reaction point in the next graft reaction issmall, and the unsaturated residue derived from the introduced diolefinprobably disappears by the crosslinking. Therefore, even if the nextgraft reaction is carried out, the sufficient activation energy of meltfluidization is not exerted, so that molding/working properties whichare intended by the present invention cannot be obtained. If the TUS/DOUis more than 200, the production ratio of the long-chain branchedcopolymer is high, so that a substantial reaction point concentration inthe undermentioned reaction step [2] is low, with the result that aconversion of the olefin copolymer (I) deteriorates.

Incidentally, the content of the unit derived from the diolefin (DOUmol%) and the total content of the unsaturated group (TUS mol%) observedin a molecular chain can be calculated as follows. In the first place,with regard to the DOU, the calculation of its content is possible fromanalysis by NMR. On the other hand, with regard to the TUS, when theunsaturated group derived from the diolefin is a vinyl group, this vinylgroup can substantially scarcely be distinguished from a vinyl groupderived from an α-olefin produced at the terminal of the molecularchain, and so the TUS is observed as the sum of both the vinyl groupsfor the time being. On the other hand, if the unsaturated group is notthe vinyl group, the TUS corresponds to the sum of the content of theunsaturated residue derived from the diolefin and the content of thevinyl group derived from the α-olefin at the terminal of the molecularchain.

Here, the vinyl type unsaturated group at the terminal of the moleculeobserved in the olefin copolymer of the present invention, or theunsaturated groups corresponding to the sum of this vinyl group and thevinyl group derived from the diolefin can easily be identified anddetermined by the measuring the infrared absorption spectra of presssheets formed at a temperature of 190° C.

    ______________________________________                                        Kind of terminal                                                                             Position of                                                    unsaturated group                                                                            absorption (cm.sup.-1)                                         ______________________________________                                        Vinylene group 963                                                            Vinylidene group                                                                             888                                                            Vinyl group    907                                                            ______________________________________                                    

In the case of the olefin copolymer in which ethylene is particularly amain monomer, the production ratio of the terminal vinyl group isusually 30 mol% or more, preferably 40 mol% or more, more preferably 50mol% or more based on the sum of the above-mentioned unsaturated groups.In this connection, the amount of the terminal vinyl group can becalculated in accordance with the formula

    n=0.114A.sub.907 /[d.t]

[wherein n is the number of the terminal vinyl groups per 100 carbonatoms, A₉₀₇ is an absorbance at 907 cm⁻ 1, d is a resin density (g/cm³),and t is the thickness of a film (mm)].

Furthermore, when the unsaturated group derived from the diolefin isdifferent from the vinyl group, the number of the unsaturated groups caneasily be calculated by replacing 0.114 which is a conversion factor ofthe above-mentioned formula with a conversion factor at a peak at whichthe unsaturated group is observed.

Additionally, in the olefin copolymer (I), usually, its melt flow rate(MFR) measured at a temperature of 190° C. under a load of 2.16 kg is inthe range of 0.001 to 2000 g/10 minutes, or its reduced viscositymeasured under conditions of a temperature of 135° C. and aconcentration of 0.2 g/dl in decalin is in the range of 0.05 to 20 dl/g.

The olefin graft copolymer (II) of the present invention can be obtainedby the reaction step [2], i.e., a step in which the olefin copolymer (I)obtained in the above-mentioned reaction step [1] is graft-polymerizedwith at least one of the above-mentioned olefins in the presence of theabove-mentioned polymerization catalyst. In the case that the reactionsteps [1] and [2] are continuously carried out without separating theolefin copolymer (I), the polymerization catalyst does not have to benewly added.

In the olefin graft copolymer (II), it is desirable that the content ofthe olefin copolymer (I) segment is in the range of 0.05 to 99% byweight, preferably 1 to 98% by weight, more preferably 2 to 95% byweight. If this content is more than 99% by weight, graft moietiesdecreases, so that the desired working properties cannot be obtained,and if it is less than 0.05% by weight, the desired working propertiescannot be obtained.

Moreover, in the olefin graft copolymer (II), usually, its melt flowrate (MFR) measured at a temperature of 190° C. under a load of 2.16 kgis in the range of 0.001 to 2000 g/10 minutes, or its reduced viscositymeasured under conditions of a temperature of 135° C. and aconcentration of 0.2 g/dl in decalin is in the range of 0.05 to 20 dl/g.In addition, its weight-average molecular weight/number-averagemolecular weight (Mw/Mn) is usually in the range of 2 to 40. That is tosay, the olefin graft copolymer (II) can be considered to be a copolymeruniformly holding a composition distribution and having a controlledmolecular weight distribution.

Furthermore, as a result of ¹³ C-NMR structure analysis, a copolymerchain produced in the reaction step [2] has a high randomness. Withregard to a relation between a melting point and a comonomer content, adrop ratio of the melting point is high at a low comonomer content, incontrast to a conventional olefin copolymer.

In the present invention, a hydrogenation treatment can be carried outin order to better the thermal stability of the olefin copolymer (I) andthe olefin graft copolymer

In this hydrogenation step, the olefin copolymer (I) obtained in thereaction step [1] and the olefin graft copolymer (II) obtained in thereaction step [2] are subjected to a hydrogenation reaction in thepresence of a hydrogenation catalyst, for example, a catalystcontaining, as main components, (A') a transition metal compound and(B') a compound capable of reacting with this transition metal compoundor its derivative to form an ionic complex, thereby preparing an olefincopolymer (III) and an olefin graft copolymer (IV) which do notsubstantially have the remaining unsaturated groups as targets.

As the above-mentioned catalyst components (A') and (B'), there can beused the same as the previously described catalyst components (A) and(B) in the above-mentioned reaction steps [1] and [2]. As the catalystin this hydrogenation step, an organic aluminum compound can be used asa component (C') together with the components (A') and (B') in a certaincase. As the organic aluminum compound of this component (C'), the sameas the previously described compound (C) in the reaction steps [1] and[2] can be used.

The components (A'), (B') and (C') in the hydrogenation step may be thesame as or different from the components (A), (B) and (C) in thereaction steps [1] and [2]. In the case that the reaction step [1] or[2] and the hydrogenation step are continuously carried out, the freshcatalyst component is not particularly required in the hydrogenationstep.

Furthermore, the use ratio of the catalyst components (A'), (B') and(C') is the same as the previously described use ratio of the catalystcomponents (A), (B) and (C) in the reaction steps [1] and [2]. Besides,in this hydrogenation step, at least one of the catalyst components canbe supported on a suitable carrier and then used, as in the case of thereaction steps [1] and [2].

No particular restriction is put on the hydrogenation catalyst which canbe used in the process of the present invention, and there can beemployed the catalysts previously mentioned in detail and catalystswhich can usually be used at the time of the hydrogenation of the olefincompound. For example, the following catalysts can be mentioned.

Examples of heterogeneous catalysts include nickel, palladium andplatinum as well as solid catalysts obtained by supporting these metalson carriers such as carbon, silica, diatomaceous earth, alumina andtitanium oxide, for example, nickel-silica, nickel-diatomaceous earth,palladium-carbon, palladium-silica, palladium-diatomaceous earth andpalladium-alumina. Examples of the nickel catalyst include Raney nickelcatalysts, and examples of the platinum catalyst include a platinumoxide catalyst and platinum black. Examples of homogeneous catalystsinclude catalysts containing metals in the groups VIII to X of theperiodic table as basic components, for example, catalysts comprising Niand Co compounds and organic metallic compounds of metals selected fromthe groups I, II and III of the periodic table such as cobaltnaphthenate-triethylaluminum, cobalt octenoate-n-butyllithium, nickelacetylacetonatotriethylaluminum, and Rh compounds.

In addition, Ziegler hydrogenation catalysts disclosed by M. S. Saloanet al. [J. Am. Chem. Soc., 85, p. 4014 (1983)] can also effectivelyused. Examples of these catalysts include the following.

Ti(O-iC₃ H₇)₄ -(iC₄ H₉)₃ Al,

Ti(O-iC₃ H₇)₄ -(C₂ H₅)₃ Al,

(C₂ H₅)₂ TiCl₂ -(C₂ H₅)₃ Al,

Cr(acac)₃ -(C₂ H₅)₃ Al

(wherein acac represents acetylacetonato),

Na(acac)₃ -(iC₄ H₉)₃ Al,

Mn(acac)₃ -(C₂ H₅)₃ Al,

Fe(acac)₃ -(C₂ H₅)₃ Al,

Ca(acac)₃ -(C₂ H₅)₃ Al, and

(C₇ H₅ COO)₃ Co-(C₂ H₅)₃ Al.

The amount of the catalyst to be used in the hydrogenation step issuitably selected so that a molar ratio of the remaining unsaturatedgroups to the hydrogenation catalyst components in the copolymers (I)and (II) may be in the range of 10⁷ :1 to 10:1, preferably 10⁶ :1 to 10²:1.

Furthermore, the charge pressure of hydrogen is suitably in the range offrom atmospheric pressure to 50 kg/cm² G. Besides, a reactiontemperature is preferably on a higher side in the range in which theolefin copolymer (I) and the olefin graft copolymer (II) do notdecompose, and it is usually selected in the range of -100° to 300° C.,preferably -50° to 200° C., more preferably 10° to 180° C.

With regard to the olefin copolymer (III) and the olefin graft copolymer(IV) obtained by this hydrogenation step, usually, its melt flow rate(MFR) measured at a temperature of 190° C. under a load of 2.16 kg is inthe range of 0.001 to 2,000 g/10 minutes, or its reduced viscositymeasured under conditions of a temperature of 135° C. and aconcentration of 0.2 g/dl in decalin is in the range of 0.05 to 20 dl/g.Moreover, it is necessary that the olefin copolymer (III) and the olefingraft copolymer (IV) should not substantially contain the remainingunsaturated groups derived from the diolefin as well as unsaturatedgroups such as terminal vinyl groups and terminal vinylidene groupsproduced at polymerization-active terminals.

Next, with regard to the thermal stability of the melt viscosity ofthese hydrogenated copolymers, in the measurement of the meltviscosities of the copolymers (III) and (IV) at a constant shear rate, atime when a load has been applied and the melt viscosity of each samplehas been stabilized is regarded as a measurement start, and in the casethat a melt viscosity at this time is represented by η*_(i) and a meltviscosity 80 minutes after the start of the measurement is representedby η*, a value of B in the formula

    (η*-η*.sub.i)/η*.sub.i ×100=B

is desirably in the range of -10 to 10, preferably -5 to 5, morepreferably -3 to 3 (incidentally, the detailed measurement procedure ofthe melt viscosity will be described hereinafter).

These hydrogenated olefin copolymer (III) and olefin graft copolymer(IV) are excellent in heat stability, can inhibit the generation of agel in blow forming or film formation, and is suitable forhigh-temperature molding.

In the present invention, as the preferable olefin graft copolymer (II)and the hydrogenated olefin graft copolymer (IV), there can be mentionedethylenic graft copolymers containing 85 to 99.99 mol% of a unit derivedfrom ethylene and having a density in the range of 0.86 to 0.97 g/cm³and a crystallization enthalpy of 10 J/g or more. The density can becontrolled in the above-mentioned range, i.e., a wide range of from anultra-low-density polyethylene to a high-density polyethylene bychanging the content of a unit derived from an α-olefin such as 1-buteneor 1-octene as well as the density and content of the olefin copolymer(I).

The crystallization enthalpy lowers owing to the increase in theα-olefin unit content, and can be controlled by presence/absence of thecrystallinity of the olefin copolymer (I), the degree of thecrystallinity and the content of the olefin copolymer (I). Furthermore,with regard to the measurement of this crystallization enthalpy, anexothermic peak of the crystallization, which can be seen when a sheetpressed at 190° C. is molten at 150° C. for 5 minutes and then cooled to-50° C. at a rate of 10° C./min, is measured by a differential scanningcalorimeter, and from the area of the crystallization peak, a valuewhich is the crystallization enthalpy is calculated.

Furthermore, in the preferable ethylenic graft copolymer in which thecontent of the unit derived from ethylene is in the range of 85 to 99.99mol%, an activation energy (Ea) of melt fluidization is present in therange of 6 to 20 kcal/mol, and a 5% weight decrease temperature in airwhich can be obtained by thermogravimetric analysis is 300° C. or more,preferably 305° C. or more, more preferably 310° C. or more. With regardto the activation energy (Ea) of the melt fluidization, a high pressureprocess low-density polyethylene has a larger Ea and is more excellentin working properties such as blow molding, as compared with astraight-chain polyethylene prepared by the use of a Ziegler catalyst.Therefore, by optionally controlling the Ea, the working properties offrom injection molding to the blow molding and the film formation can beimparted, and therefore the Ea is an extremely important index.

Incidentally, the activation energy (Ea) can be calculated as follows.That is to say, the frequency dependence (10⁻² to 10² rad/sec) ofdynamic viscoelasticity at each of measurement temperatures of 150° C.,170° C., 190° C., 210° C. and 230° C. is measured, and the activationenergy (Ea) is then calculated from shift factors of G', G" at therespective temperatures and a reciprocal of an absolute temperature inaccordance with the Arrhenius' equation on the basis of a standardtemperature of 170° C. by the use of a temperature·time conversion rule.

Furthermore, with regard to the thermal stability, the polymer having acarbon-carbon unsaturated group is usually low in thermal stability, andis poor in molding/working properties and weathering resistance.Therefore, an intricate treatment using additives is necessary, but inthe olefin graft copolymers (II) and (IV) of the present invention,their 5% weight decrease temperatures are 300° C. or more, preferably305° C. or more, more preferably 310° C. or more, and hence theabove-mentioned problem can be solved. The 5% weight decreasetemperature means a temperature at the time of 5% weight decrease in thecase that heating is carried out at a rate of 10° C./min at an air flowrate of 300 ml/min. This improvement of the thermal stability can begiven by the decrease in the unsaturated groups in the copolymer (II) bythe graft polymerization and the copolymer (IV) by the hydrogenationtreatment.

Next, as the preferable olefin copolymer (I), olefin graft copolymer(II), hydrogenated olefin copolymer (III) and hydrogenated olefin graftcopolymer (IV), there can be mentioned propylene copolymers in which thecontent of a unit derived from propylene is in the range of 85 to 99.99mol%, the crystallization enthalpy is 10 J/g or more and the activationenergy (Ea) of the melt fluidization is in the range of 12 to 27kcal/mol. In the case of the olefin graft copolymer (II), the reactionsteps [1] and [2] may continuously or simultaneously be carried out, andat least one of the olefins may be grafted on the olefin copolymer (I)obtained in the step [1] in the presence of the polymerization catalyst.

In the above-mentioned propylene copolymers, the activation energy (Ea)of the melt fluidization is sufficiently improved and the workingproperties are more excellent as compared with a propylene homopolymerhaving a substantially equal weight-average molecular weight. Moresuitable are the propylene copolymers in which the Ea is in the range of12 to 27 kcal/mol, preferably 15 to 25 kcal/mol.

The characteristics of the olefin graft copolymers (II) and (IV) of thepresent invention depend upon the kind of olefin which is used in thereaction step [1] and the kind of olefin which is used in the reactionstep [2]. For example, a polymer obtained by using ethylene or ethyleneand an α-olefin as the olefin in the reaction step [1] and usingethylene as the α-olefin in the reaction step [2] is an HDPE having theimproved molding/working properties. Moreover, a polymer obtained byusing ethylene or ethylene and an α-olefin in the reaction step [1] andusing ethylene and an α-olefin in the reaction step [2] is a novelhigh-performance LDPE, VLDPE (an ultra-low-density polyethylene) orL-LDPE in which the molding/working properties are controlled and towhich a good transparency and heat-sealing properties are imparted.

Furthermore, a polymer obtained by using ethylene or ethylene and anα-olefin in the reaction step [1] and introducing an isotacticpolypropylene segment, a branched α-olefin (e.g., 4-methylpentene-1 orthe like) polymer segment, or an isotactic, sydiotactic or atacticpolystyrene segment in the reaction step [2] is a novel thermoplasticelastomer, which is useful for modification, for example, toughening orsoftening of the above-mentioned polymer produced in the reaction step[2].

In addition, in the case that propylene or propylene and an α-olefin areused in the reaction step [1] and propylene is used in the reaction step[2], a branched propylene copolymer having the improved molding/workingproperties can be obtained, and by changing polymerization conditionsand the amount of the diolefin to be used, the copolymer in whichcrystallinity and the Ea are controlled can be prepared.

The olefin copolymer (I), the olefin graft copolymer (II), thehydrogenated olefin copolymer (III) and the hydrogenated olefin graftcopolymer (IV) of the present invention can each be mixed with anotherthermoplastic resin and then used. Examples of the other thermoplasticresin include polyolefin resins, polystyrene resins, condensation serieshigh-molecular weight polymers and addition polymerization serieshigh-molecular weight polymers. Typical examples of the polyolefinresins include high-density polyethylenes, low-density polyethylenes,poly-3-methylbutene-1, poly-4-methylpentene-1, straight-chainlow-density polyethylenes obtained by the use of 1-butene, 1-hexene,1-octene, 4-methylpentene-1 and 3-methylbutene-1 as comonomercomponents, ethylene-vinyl acetate copolymers, saponified ethylene-vinylacetate copolymers, ethylene-acrylic acid copolymers, ethylene-acrylicacid ester copolymers, ethylenic ionomers and polypropylene. Typicalexamples of the polystyrene resins include general-purpose polystyrenes,isotactic polystyrenes and (rubber modified) high-impact polystyrenes.Typical examples of the condensation series high-molecular weightpolymers include polyacetal resins, polycarbonate resins, polyamideresins such as 6-nylon and 6,6-nylon, polyester resins such aspolyethylene terephthalates and polybutylene terephthalates,polyphenylene oxide resins, polyimide resins, polysulfone resins,polyethersulfone resins and polyphenylene sulfide resins. Examples ofthe addition polymerization series high-molecular weight polymersinclude polymers obtained from polar vinyl monomers and polymersobtained from diene monomers, typically, polymethyl methacrylate,polyacrylonitrile, acrylonitrile-butadiene copolymer,acrylonitrile-butadiene-styrene copolymer, diene polymers in which adiene chain is hydrogenated, and thermoplastic elastomers. Among thesethermoplastic resins, the polyolefin resins are suitable.

Next, the present invention will be described in more detail withrespect to examples.

EXAMPLE 1

(1) Preparation of methylaluminoxane

In a 500-ml glass container which had been purged with argon were placed200 ml of toluene, 17.7 g (71 mmols) of copper sulfate pentahydrate(CuSO₄.5H₂ O) and 24 ml (250 mmols) of trimethylaluminum, and themixture was then reacted at 40° C. for 8 hours. Afterward, from asolution obtained by removing solid components, toluene was furtherdistilled off under reduced pressure to obtain 6.7 g of a catalysticproduct (methylaluminoxane). According to measurement by a cryoscopicmethod, the molecular weight of the product was 610. Furthermore, a highmagnetic field component by ¹ H-NMR measurement, i.e., a methyl protonsignal based on a (Al--CH₃) bond was observed in the range of 1.0 to-0.5 ppm under a tetramethylsilane standard according to the observationof its proton nuclear magnetic resonance spectrum at room temperature ina toluene solution. The proton signal (0 ppm) of tetramethylsilane waspresent in an observation range based on the methyl proton having theAl--CH₃ bond. Therefore, this methyl proton signal based on the Al--CH₃bond was measured on the basis of the methyl proton signal 2.35 ppm oftoluene under the tetramethylsilane standard, and the high magneticfield components (i.e., -0.1 to -0.5 ppm) were separated from othermagnetic field components (i.e., 1.0 to -0.1 ppm). At this time, thecontent of the high magnetic field components were 43% of the total.

(2) Preparation of copolymers

(i) Preparation of a copolymer (I)

In a 500-ml pressure glass container were placed 100 ml of toluene, 30mmols of divinylbenzene (the content of m-isomer and p-isomer=55 wt %),1 mmol of triisobutylaluminum and 2 mmols of methylaluminoxane preparedin the above-mentioned (1) in a nitrogen atmosphere, and the solutionwas then heated up to 80° C. An ethylene pressure of 0.6 kg/cm² G wasapplied thereto to saturate the solution with ethylene. Moreover, 10micromols of dicyclopentadienylzirconium dichloride was added thereto tostart copolymerization. While the ethylene pressure was maintained at0.6 kg/cm² G, reaction was carried out for 150 minutes. At the end ofthe reaction, the polymer was uniformly dissolved, and it was thenprecipitated again in a large amount of methanol and collected byfiltration. Afterward, vacuum drying was carried out at 40° C. for 20hours to obtain 2.3 g of a white polymer.

A weight-average molecular weight (Mw) and a molecular weightdistribution (Mw/Mn) of this copolymer were measured under the followingconditions, and as a result, Mw=5,670 and Mw/Mn=6.6.

Device:Waters ALC/GPC 150C

Column: Toso Co., Ltd., TSK HM+GMH6×2

Solvent: 1,2,4-trichlorobenzene

Temperature: 135° C.

Flow rate: 1 ml/min (in terms of polyethylene)

Furthermore, in the infrared absorption spectrum (IR) of this copolymer,the absorption of a vinyl group was observed at about 1,630 cm⁻¹ andabout 907 cm⁻¹, and the absorption of a divinylbenzene residue waspresent at about 1,602 cm⁻¹.

The content of the divinylbenzene unit measured by ¹ H-NMR was 0.62mol%, and the amount of the vinyl group observed at IR 907 cm⁻¹ was 0.44mol%. Therefore, a total unsaturated group content/divinylbenzene unitcontent (molar ratio) was 0.71.

(ii) Preparation of a copolymer (II)

0.55 g of the copolymer (I) obtained in the above-mentioned (i) wasdissolved in 80 ml of toluene, and nitrogen bubbling was then carriedout for 30 minutes. Next, 0.5 mmol of triisobutylaluminum and 1 mmol ofmethylaluminoxane prepared in the above-mentioned (1) were added to thesolution, and it was then heated up to 80° C. An ethylene pressure of 3kg/cm² G was applied thereto, and the solution was then saturated withethylene. Moreover, 2 micromols of dicyclopentadienylzirconiumdichloride were added thereto to start copolymerization, and while theethylene pressure was maintained at 3 kg/cm² G, reaction was carried outfor 170 minutes.

After the completion of the reaction, the solution was poured intomethanol, followed by filtration, to collect a graft copolymer (II).Next, vacuum drying was carried out at 80° C. for 4 hours to obtain 15.6g of a white polymer. The weight ratio of the yield of the copolymer (I)to that of the graft copolymer (II) was 1:28.4. The weight-averagemolecular weight (Mw) and the molecular weight distribution (Mw/Mn) ofthis copolymer (II) were 93000 and 9.1, respectively, and itsdistribution was in the form of a single peak. Moreover, the reducedviscosity of the copolymer measured under conditions of a temperature of135° C. and a concentration of 0.2 g/dl in decalin was 2.19 dl/g.

(3) Evaluation of the graft copolymer (II)

(i) Crystallization enthalpy (ΔH) and melting point (Tm)

As a device, a differential scanning calorimeter DSC7 made by PerkinElmer Co., Ltd. was used, and measurement was made in the followingmanner. That is to say, there were measured an exothermic peak of thecrystallization seen when a sheet pressed at 190° C. was molten at 150°C. for 5 minutes and then cooled to -50° C. at a rate of 10° C./min, andan endothermic peak of melting seen at the time of a temperature rise of10° C./min. The melting point (Tm) was 132.7° C., and thecrystallization enthalpy (ΔH) was 186 J/g.

(ii) Density

The density of a pressed film was measured with a density gradient tube,and as a result, it was 0.967 g/cm³.

(iii) Activation energy (Ea) of the melt fluidization

As a device, RMS E-605 made by Rheometrics Co., Ltd. was used, andmeasurement was made in the following manner. That is to say, thefrequency dependence (10⁻² to 10² rad/sec) of dynamic viscoelasticity ateach of measurement temperatures of 150° C., 170° C., 190° C., 210° C.and 230° C. was measured, and the activation energy (Ea) was thencalculated from shift factors of G', G" at the respective temperaturesand a reciprocal of an absolute temperature in accordance with theArrhenius' equation on the basis of a standard temperature of 170° C. bythe use of a temperature·time conversion rule.

As a result, Ea was 8.9 kcal/mol.

(iv) Thermal stability

As a device, a thermogravimetric analyzer SSC 5000 made by SeikoElectronics Co., Ltd. was used, and a weight decrease in the case thattemperature was raised at a rate of 10° C./min at an air flow rate of300 ml/min was measured to determine a temperature at the time of the 5%weight decrease. As a result, the thermal stability was 337° C.

EXAMPLE 2

(1) Preparation of a copolymer

(i) Preparation of a copolymer (I)

The same procedure as in Example 1-(2)-(i) was carried out except thatin Example 1-(2)-(i), divinylbenzene was replaced with 10 mmols of1,5-hexadiene and 0.5 mmol of triisobutylaluminum, 2 micromols ofdicyclopentadienylzirconium dichloride and an ethylene pressure of 0.4kg/cm² G were employed, to prepare a copolymer (I). As a result, 1.7 gof the copolymer (I) was obtained.

In this copolymer (I), Mw was 5630 and Mw/Mn was 6.3, and the content ofa 1,5-hexadiene unit was 1.4 mol%. In addition, the content of a vinylgroup corresponding to an unsaturated group in a molecular chain wascalculated from an absorbance at 907 cm⁻¹ which appeared on an infraredabsorption spectrum, and as a result, it was 0.08 mol%. Therefore, atotal unsaturated group content/1,5-hexadiene unit content molar ratiowas 0.057.

(ii) Preparation of a graft copolymer (II)

The same procedure as in Example 1-(2)-(ii) was carried out except thatin Example 1-(2)-(ii), 1 g of the copolymer (I) prepared in theabove-mentioned (i) was used as the copolymer, to prepare a graftcopolymer (II), whereby 12.4 g of the white polymer was obtained.

The weight ratio of the copolymer (I) to the graft copolymer (II) was1:11.4. Furthermore, the weight-average molecular weight (Mw) of thegraft copolymer (II) was 58,600, and a molecular weight distribution(Mw/Mn) was 15.0, and the distribution of the molecular weight was inthe form of a single peak.

(2) Evaluation of the graft copolymer (II)

The same procedure as in Example 1-(3) was carried out. The results areshown in Table 1.

EXAMPLE 3

(1) Preparation of a copolymer (I)

In a 10-liter stainless steel pressure autoclave were placed 40 ml oftoluene, 2 mmols of divinylbenzene, 0.5 mmol of triisobutylaluminum, 5mmols of methylaluminoxane prepared in Example 1-(1) and 0.03 mmol ofpentamethylcyclopentadienyltitanium trimethoxide [Cp*Ti(OMe)₃ ], and themixture was then heated up to 80° C. Next, ethylene was added to thesolution under a constant pressure of 4 kg/cm² G to carry outcopolymerization for 60 minutes, whereby 15.6 g of the copolymer (I) wasobtained.

The weight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this copolymer (I) were 14,500 and 23.0,respectively. Furthermore, the content of a divinylbenzene unit was 0.11mol%, and the content of a terminal vinyl group at 907 cm⁻¹ whichappeared on an infrared absorption spectrum was 0.11 mol%. In addition,the absorption of a terminal α-olefin was observed at 1,646 cm⁻¹, andaccording to ¹ H-NMR its existent amount was 0.72 mol%. Therefore, atotal unsaturated group content/divinylbenzene unit content molar ratiowas 7.55.

(2) Preparation of a graft copolymer (II)

The same procedure as in Example 1-(2)-(ii) was carried out except thatin Example 1-(2)-(ii), 1 g of the copolymer (I) prepared in theabove-mentioned (1) was used as the copolymer (I), to prepare a graftcopolymer (II), whereby 7.2 g of the white polymer was obtained.

The weight ratio of the copolymer (I) to the graft copolymer (II) was1:16.2. Furthermore, the weight-average molecular weight (Mw) of thegraft copolymer (II) was 123,000, and a molecular weight distribution(Mw/Mn) was 8.5, and the distribution of the molecular weight was in theform of a single peak. Moreover, the reduced viscosity of the copolymermeasured at a temperature of 135° C. and a concentration of 0.2 g/dl indecalin was 2.83 dl/g.

(3) Evaluation of the graft copolymer (II)

The same procedure as in Example 1-(3) was carried out. The results areshown in Table 1.

EXAMPLE 4

(1) Preparation of tri-n-butylammonium tetrakis(pentafluorophenyl)borate

Pentafluorophenyllithium prepared from bromopentafluforobenzene (152mmols) and butyllithium (152 mmols) was reacted with 45 mmols of borontrichloride in hexane to obtain tris(pentafluorophenyl)boron in the formof a white solid. Next, 41 mmols of this tris(pentafluorophenyl)boronwas reacted with 41 mmols of pentafluorophenyllithium to obtainlithiumtetrakis(pentafluorophenyl)boron in the form of a white solid.

Next, 16 mmols of lithiumtetrakis(pentafluorophenyl)boric acid wasreacted with 16 mmols of tri-n-butylammonium hydrochloride in water toobtain 12.8 mmols of tri-n-butylammoniumtetrakis(pentafluorophenyl)borate in the form of a white solid.

(2) Preparation of a graft copolymer (II)

1 g of the copolymer (I) prepared in Example 1-(2)-(i) was dissolved in80 ml of toluene, and nitrogen bubbling was then carried out for 20minutes. Next, to this solution were added 8 ml of 1-octene, 0.5 mmol oftriisobutylaluminum, 6 micromols of tri-n-butylammoniumtetrakis(pentafluorophenyl)borate prepared in the abovementioned (1) and2 micromols of dicyclopentadienyl-zirconium dichloride, followed byheating the solution up to 70° C. Next, an ethylene pressure of 3 kg/cm²G was applied thereto to start graft copolymerization, and reaction wascarried out for 30 minutes while the pressure was constantly maintained.

The amount of the obtained graft copolymer (II) was 13 g, and the weightratio of the copolymer (I) to the graft copolymer (II) was 1:12. The1-octene unit content of this graft copolymer (II) was 1.8 mol%, and thereduced viscosity of the copolymer measured at a temperature of 135° C.and a concentration of 0.2 g/dl in decalin was 1.53 dl/g.

(3) Evaluation of the graft copolymer (II)

The same procedure as in Example 1-(3) was carried out. The results areshown in Table 1.

EXAMPLE 5

(1) Preparation of a copolymer (I)

In a 1-liter stainless steel pressure autoclave were placed 600 ml oftoluene, 2 ml of 1-octene, 2 mmols of norbornadiene, 2 mmols oftriisobutylaluminum and 4 mmols of methylaluminoxane prepared in Example1-(1), followed by heating the solution up to 85° C. Next, an ethylenepressure of 0.5 kg/cm² G was applied thereto to saturate the solutionwith ethylene, and 4 micromols of dicyclopentadienylzirconium dichloridewas then added thereto to start copolymerization, and while the ethylenepressure was maintained at 0.5 kg/cm² G, the polymerization was carriedout for 30 minutes. After the completion of the reaction, the solutionwas poured into methanol, followed by filtration, to collect a copolymer(I). Next, vacuum drying was carried out at 40° C. for 8 hours to obtain1.1 g of the copolymer (I).

The weight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this copolymer (I) were 28,500 and 3.4,respectively. The content of a norbornadiene unit measured by NMR was0.36 mol%, and the content of an unsaturated group derived from anorbornadiene residue observed at 963 cm⁻¹ on an infrared absorptionspectrum was 0.19 mol%. Furthermore, the absorption based on a vinylgroup at the terminal of a molecular chain at 907 cm⁻¹ on the infraredabsorption spectrum was observed, and its content was 0.53 mol%.Therefore, a total unsaturated group content/norbornadiene unit content(molar ratio) was 2.0.

(2) Preparation of a graft copolymer (II)

In a 1-liter stainless steel pressure autoclave, 0.9 g of the copolymer(I) obtained in the above-mentioned (1) was dissolved in 600 ml oftoluene, and toluene was distilled off under reduced pressure at 70° C.for 60 minutes and then 400 ml of toluene was newly added thereto. Next,20 ml of 1-octene, 1 mmol of triisobutylaluminum and 2 mmols ofmethylaluminoxane prepared in Example 1-(1) were added thereto, followedby heating the solution up to 85° C. Next, an ethylene pressure of 5kg/cm² G was applied thereto to saturate the solution with ethylene, and2 micromols of dicyclopentadienylzirconium dichloride was then addedthereto to start copolymerization, and while the ethylene pressure wasmaintained at 5 kg/cm² G, the polymerization was carried out for 60minutes. After the completion of the reaction, the solution was pouredinto methanol, followed by filtration to collect a copolymer (II). Next,vacuum drying was carried out at 80° C. for 4 hours to obtain 73.5 g ofthe graft copolymer (II).

The weight ratio of the yield of the copolymer (I) to that of the graftcopolymer (II) was 1:82. The weight-average molecular weight (Mw) andthe molecular weight distribution (Mw/Mn) of this copolymer (II) were115,600 and 3.2, respectively, and this distribution was in the form ofa single peak. Moreover, the reduced viscosity of the copolymer measuredunder conditions of a temperature of 135° C. and a concentration of 0.2g/dl in decalin was 1.81 dl/g.

(3) Evaluation of the graft copolymer (II)

The same procedure as in Example 1-(3) was carried out. The results areshown in Table 1.

                  TABLE 1                                                         ______________________________________                                                  Melting     Crystallization                                                   Point (Tm)  Enthalpy (ΔH)                                                                       Density                                               (°C.)                                                                              (J/g)       (g/cm.sup.3)                                ______________________________________                                        Example 2 135.2       208         0.962                                       Example 3 133.2       200         0.958                                       Example 4 114.0       123         0.920                                       Example 5 121.2       120         0.931                                       ______________________________________                                                    Activation Energy (Ea)                                                                        Thermal                                                       of Melt Fluidization                                                                          Stability                                                     (kcal/mol)      (°C.)                                      ______________________________________                                        Example 2   9.6             337                                               Example 3   9.2             330                                               Example 4   9.8             325                                               Example 5   15.8            340                                               ______________________________________                                    

EXAMPLE 6

Dimethylsilylenebis(2,4-dimethylcyclopentadienyl)zirconium dichloride(its structure had already been confirmed by ¹ H-NMR) prepared by ausual method was used to carry out the polymerization of propylene.

In a 1-liter reactor equipped with a stirrer were placed 400 ml oftoluene, 4 micromols ofdimethylsilylenebis(2,4-dimethylcyclopentadienyl)zirconium dichloride, 2mmols of trisiobutylaluminum, 4 mmols of methylaluminoxane prepared inExample 1-(1) and 4 mmols of norbornadiene, and polymerization was thencarried out at 30° C. for 90 minutes under a propylene pressure of 7.0kg/cm² G. After the completion of the reaction, an unreacted gas wasremoved, and the polymer was washed with acidic methanol, sufficientlywashed with methanol, and then dried to obtain 62.5 g of the polymer.

In this polymer, the content of a norbornadiene unit was 0.57 mol%, anda total unsaturated group content/norbornadiene unit content (molarratio) was 5.97. Furthermore, as a result of GPC measurement, theweight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of the polymer were 183,000 and 3.2, respectively,and the reduced viscosity of the polymer measured under conditions of atemperature of 135° C. and a concentration of 0.2 g/dl in decalin was3.15 dl/g. Additionally, in the polymer, a melting point (Tm) was 158.9°C., a crystallization enthalpy (ΔH) was 82.6 J/g, and the activationenergy (Ea) of melt fluidization was 19.5 kcal/mol.

EXAMPLE 7

10 g of anhydrous magnesium chloride was mixed with 1.9 ml of a toluenesolution containing 0.38 g of triisobutylaluminum, and the mixture wasthen placed in a vibration mill (the internal volume of a pot=1,000 ml,SUS balls having a diameter of 12.7 mm=2 kg), and they were groundtogether for 17 hours. Furthermore, 2.2 g of tri-n-butylammoniumtetrakis(pentafluorophenyl)borate prepared in Example 4-(1) and 0.95 gof dimethylsilylenebis(2,4-dimethylcyclopentadienyl)zirconium dichlorideused in Example 6 were placed in the vibration mill, and they were thenground together for 4 hours.

200 mg of the above-mentioned ground material was dispersed in 100 ml ofhexane, and 0.46 g of triisobutyl-aluminum was then added thereto. Afterstirring at room temperature for 17 hours, a supernatant liquid wasremoved, and the material was washed with 100 ml of hexane to prepare asolid catalyst.

Next, in a 1-liter reactor equipped with a stirrer were placed 400 ml oftoluene, 25 mg of the above-mentioned solid catalyst and 5 mmols ofnorbornadiene, and polymerization was then carried out at 40° C. under apropylene pressure of 8 kg/cm² G. After the completion of the reaction,unreacted propylene was removed, and the resultant polymer was taken outand then dried to obtain 92.5 g of the polymer.

In this polymer, the content of a norbornadiene unit was 0.61 mol%, anda total unsaturated group content/norbornadiene unit content (molarratio) was 3.40. Furthermore, as a result of GPC measurement, theweight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this polymer were 136,420 and 2.70,respectively, and the reduced viscosity of the polymer measured underconditions of a temperature of 135° C. and a concentration of 0.2 g/dlin decalin was 2.08 dl/g. Additionally, in the polymer, a melting point(Tm) was 158.6° C., a crystallization enthalpy (ΔH) was 71.9 J/g, andthe activation energy (Ea) of melt fluidization was 17.9 kcal/mol.

Comparative Example 1

The same procedure as in Example 8 was carried out except that anynorbornadiene was not used, to obtain 89.7 g of a polymer.

As a result of GPC measurement, this polymer had a weight-averagemolecular weight (Mw) of 88,000, a molecular weight distribution (Mw/Mn)of 2.02, a melting point (Tm) of 159.3° C. and a crystallizationenthalpy (ΔH) of 105.4 J/g. In addition, the reduced viscosity of thepolymer measured under conditions of a temperature of 135° C. and aconcentration of 0.2 g/dl in decalin was 1.64 dl/g, and the activationenergy (Ea) of melt fluidization was 8.6 kcal/mol.

EXAMPLE 8

(1) Preparation of a copolymer (I)

In a 1-liter stainless steel pressure autoclave were placed 600 ml oftoluene, 80 mmols of p-(3-butenyl)styrene, 0.5 mmol oftriisobutylaluminum, 2 mmols of methylaluminoxane prepared in Example1-(1) and 2 micromols of dicyclopentadienylzirconium dichloride,followed by heating the solution up to 70° C. Afterward, propylene wasintroduced at 3 kg/cm² G, and ethylene was further continuouslyintroduced at 3 kg/cm² G to carry out polymerization for 60 minutes.After the completion of the polymerization, the reaction system wascooled and the pressure was released, and the resultant copolymer (I)was precipitated again in a large amount of methanol and then collectedby filtration. Next, vacuum drying was carried out at 50° C. for 10hours to obtain 105 g of the copolymer (I).

(2) Evaluation of the graft copolymer (I)

In the copolymer (I), a melt flow rate (MFR) measured under conditionsof a temperature of 190° C. and a load of 2.16 kg was 14.5 g/10 minutes,and the reduced viscosity of the copolymer measured under conditions ofa temperature of 135° C. and a concentration of 0.2 g/dl in decalin was1.10 dl/g. As a result of GPC measurement, the weight-average molecularweight (Mw) and the molecular weight distribution (Mw/Mn) of thiscopolymer were 49,600 and 4.1, respectively.

Furthermore, on the infrared absorption spectrum (IR) of this copolymer(I), absorptions attributable to a terminal vinylidene group and aterminal vinyl group were observed at about 888 cm⁻¹ and about 907 cm⁻¹,respectively, and in addition, an absorption attributable to a butenylresidue of p-(3-butenyl)styrene was observed at about 1,680 cm⁻¹. Thecontents of the comonomer units were calculated from the absorbances ofthe respective peaks, and as a result, the content of the propylene unitwas 18.8 mol% and that of the p-(3-butenyl)styrene unit was 0.16 mol%.The total amount of unsaturated groups measured by the IR spectrum was0.32 mol%, and so a total unsaturated group content/diolefin unitcontent (molar ratio) was 2.0.

(3) Preparation of a copolymer (III)

In a 1-liter stainless steel pressure autoclave, 20 g of the copolymer(I) was dissolved in 600 ml of toluene at 70° C., and 0.25 mmol oftriisobutylaluminum, 1 mmol of methylaluminoxane and 0.5 micromol ofdicyclopentadienyl-zirconium dichloride were added thereto. Afterward,hydrogen was introduced at 3 kg/cm² G to carry out a hydrogenationreaction for 180 minutes. After the completion of the reaction, thereaction system was cooled and the pressure was released, and theresultant copolymer (III) was precipitated again in a large amount ofmethanol and then collected by filtration. Next, vacuum drying wascarried out at 80° C. for 10 hours to obtain 19.8 g of the copolymer(III).

(4) Evaluation of the graft copolymer (III)

In the copolymer (III), a melt flow rate (MFR) measured under conditionsof a temperature of 190° C. and a load of 2.16 kg was 12.4 g/10 min, andthe reduced viscosity of the copolymer measured under conditions of atemperature of 135° C. and a concentration of 0.2 g/dl in decalin was1.21 dl/g.

The weight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this copolymer (III) were measured, and as aresult, Mw=49,500 and Mw/Mn =4.2, and hence the Mw and the Mw/Mn of thecopolymer (III) were substantially the same as in the copolymer (I).

However, on an infrared absorption spectrum (IR) of this copolymer(III), any absorptions attributable to a terminal vinylidene group atabout 888 cm⁻¹ a terminal vinyl group at about 907 cm⁻¹ and a butenylresidue at about 1,680 cm⁻¹ were not observed. On the other hand, theintensity of the absorption peak attributable to the benzene ring ofp-(3-butenyl)styrene seen at about 1,512 cm⁻¹ was scarcely differentfrom the spectrum of the copolymer (I), and the content of ap-(3-butenyl)styrene unit was 0.16 mol%.

In addition, the thermal stability of the copolymer (III) was measuredby the use of the undermentioned device and conditions, when a meltviscosity 80 minutes after the start of the measurement was representedby η* and a melt viscosity at the start of the measurement wasrepresented by η*_(i),

    B=(η*-η*.sub.i)/η*.sub.i ×100=2.3.

Incidentally, B of the copolymer (I) which did not undergo thehydrogenation was 29.2.

[Measurement procedure of thermal stability]

A capilograph made by Toyo Seiki Works Co., Ltd. (capillary:length=10mm, diameter=1 mm and a barrel diameter=9.6 mm) was used, andmeasurement was made under conditions of a measurement temperature inair of 190° C., an extrusion rate of 2 mm/min and a shear rate of 24.3sec⁻¹.

About 15 g of a powdery sample was put in a barrel heated up to 190° C.,and the sample was then preheated for 15 minutes to melt the sample.Afterward, a certain load was applied to the sample so that theextrusion rate might be constant, and after 10 minutes had elapsed tomake an extrusion state stable, the measurement of a melt viscosity wasstarted. The melt viscosity at this time was represented by η*_(i) andthe melt viscosity 80 minutes after the start of the measurement wasrepresented by η*.

EXAMPLE 9

(1) Preparation of copolymers (I), (II)

In a 1-liter stainless steel pressure autoclave were placed 600 ml oftoluene, 20 ml of 1-octene, 10 mmols of 1,5-hexadiene, 2 mmols oftriisobutylaluminum, 4 mmols of methylaluminoxane prepared in Example1-(1) and 4 micromols of dicyclopentadienylzirconium dichloride,followed by heating the solution up to 85° C. Afterward, ethylene wascontinuously introduced at 5 kg/cm² G to carry out polymerization for 60minutes. After the completion of the polymerization, the pressure in thereaction system was released, and the resultant copolymer wasprecipitated again in a large amount of methanol and then collected byfiltration. Next, vacuum drying was carried out at 50° C. for 10 hoursto obtain 87 g of the copolymer (I).

Hydrogen was introduced, at 3 kg/cm² G, into the copolymer obtainedunder the above-mentioned conditions, and a hydrogenation reaction wasthen performed at 85° C. for 120 minutes. At this time, the freshcatalyst component was not added. After the completion of the reaction,the reaction system was cooled and the pressure was released, and theresultant copolymer (III) was precipitated again in a large amount ofmethanol and then collected by filtration. Next, vacuum drying wascarried out at 80° C. for 10 hours to obtain 89 g of the copolymer(III).

(2) Evaluation of the graft copolymer (I)

In the copolymer (I), a melt flow rate (MFR) measured under conditionsof a temperature of 190° C. and a load of 2.16 kg was 1.15 g/10 min, andthe reduced viscosity of the copolymer measured under conditions of atemperature of 135° C. and a concentration of 0.2 g/dl in decalin was1.68 dl/g.

The weight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this copolymer (I) were measured, and as aresult, Mw=111,700 and Mw/Mn=2.9.

Furthermore, on the infrared absorption spectrum (IR) of this copolymer(I), absorptions attributable to a terminal vinylidene group and aterminal vinyl group were observed at about 888 cm⁻¹ and about 907 cm⁻¹respectively, and also on a proton NMR spectrum, peaks attributable tounsaturated groups were observed at 5 to 6 ppm.

The content of a 1,5-hexadiene unit was 1.4 mol%, and the total amountof the unsaturated groups measured by the IR spectrum was 0.09 mol%.Therefore, a total unsaturated group content/diolefin unit content(molar ratio) was 0.064.

(3) Evaluation of the copolymer (III)

In the copolymer (III), a melt flow rate (MFR) measured under conditionsof a temperature of 190° C. and a load of 2.16 kg was 1.09 g/10 min, andthe reduced viscosity of the copolymer measured under conditions of atemperature of 135° C. and a concentration of 0.2 g/dl in decalin was1.70 dl/g.

The weight-average molecular weight (Mw) and the molecular weightdistribution (Mw/Mn) of this copolymer (III) were measured, and as aresult, Mw=120,800 and Mw/Mn=3.0.

On an IR spectrum and a proton NMR spectrum of this copolymer (III), anypeak attributable to an unsaturated group was not observed. In addition,a 1,5-hexadiene unit content was 1.4 mol%, as in the case of thecopolymer (I).

Furthermore, the thermal stability of the copolymer (III) was measuredin the same manner as in Example 9-(4), and as a result,

    (η*-η*.sub.i)/η*.sub.i ×100=-0.98.

On the other hand, the thermal stability of the copolymer (I) wassimilarly measured, and as a result, a melt viscosity increased withtime and in consequence,

    (η*-η*.sub.i)/η*.sub.i ×100=20.8.

Possibility of Industrial Utilization

According to the present invention, an olefin copolymer can be obtainedwhich can optionally control the activation energy of melt fluidizationand in which high-speed molding is possible to lower a working cost anda high-speed film formation is possible by the control of a molecularweight distribution and which has an excellent thermal stability,transparency and uniformity. In consequence, a high-performance VLDPE,LDPE, L-LDPE and HDPE can be easily obtained, and a novel branchedpropylene polymer and a novel olefin elastomer can also be obtained.

In particular, the olefin copolymer of the present invention which hasbeen subjected to a hydrogenation treatment is substantially free froman unsaturated group, is excellent in thermal stability, and can inhibitthe generation of a gel in blow molding and film formation, and so thiskind of olefin copolymer is suitable for high-temperature molding.

In addition, the olefin copolymer of the present invention is alsouseful as a compatibilizing agent for other thermoplastic resins.

We claim:
 1. An olefin graft copolymer prepared by the graftpolymerization of an olefin copolymer and an olefin, wherein said olefincopolymer comprises a unit (1) which is at least one member selectedfrom the group consisting of ethylene, α-olefins having 3 to 20 carbonatoms and cyclic olefins and a unit (2) which is a diolefin and in whicha weight-average molecular weight is in the range of 200 to 800,000, thecontent of the diolefin unit is in the range of 0.002 to 30 mol%, and arelation between the content of the diolefin unit (DOU mol%) and thetotal content of unsaturated groups observed in a molecular chain (TUSmol%) meets the formula

    0.001<TUS/DOU<200.


2. 2. The olefin graft copolymer according to claim 2, wherein unit (1)is ethylene and the content of said unit (1) is in the range of 85 to99.99 mol%, a density is in the range of 0.86 to 0.97 g/cm³, and theactivation energy (Ea) of melt fluidization is in the range of 6 to 20kcal/mol.
 3. A process for preparing the olefin graft copolymerdescribed in claim 1 which comprises the steps of copolymerizing atleast one member selected from the group consisting of ethylene,α-olefins having 3 to 20 carbon atoms and cyclic olefins and a diolefinin the presence of a polymerization catalyst containing, as maincomponents, (A) a transition metal compound and (B) a compound capableof reacting with the transition metal compound of the component (A) toform an ionic complex, whereby an olefin copolymer is formed, and thenfurther graft-polymerizing the copolymer and an olefin in the presenceof the polymerization catalyst.
 4. The olefin graft copolymer accordingto claim 1, wherein a melt flow rate (MFR) measured under conditions ofa temperature of 190° C. and a load of 2.16 kg is in the range of 0.001to 2,000 g/10 min, or the reduced viscosity of the copolymer measuredunder conditions of a temperature of 135° C. and a concentration of 0.2g/dl in declain is in the range of 0.05 to 20 dl/g.
 5. The olefin graftcopolymer of claim 1, wherein unit (1) is propylene and the content ofsaid unit (1) is in the range of 85 to 99.99 mol.%, and the activationenergy (Ea) of melt fluidization is in the range of 12 to 27 kcal.mol.6. The preparation process according to claim 3, wherein the diolefin isat least one polyfunctional monomer selected from the group consistingof cyclic diene compounds and compounds obtained from at least twosimilar or different kinds of residues selected from the groupconsisting of an α-olefin residue, a styrene residue and a cyclic olefinresidue.
 7. The process for preparing a substantially unsaturatedgroup-free olefin graft copolymer prepared by hydrogenating the olefingraft copolymer described in claim 1, wherein the olefin graft copolymerobtained by a process comprising copolymerizing at least one memberselected from the group consisting of ethylene, α-olefins having 3 to 20carbon atoms and cyclic olefins and a diolefin in the presence of apolymerization catalyst containing, as main components, (A) a transitionmetal compound and (B) a compound capable of reacting with thetransition metal compound of the component (A) to form an ionic complex,wherein an olefin copolymer is formed, and then furthergraft-polymerizing the copolymer and an olefin in the presence of thepolymerization catalyst, is hydrogenated in the presence of thehydrogenation catalyst.
 8. The process according to claim 7, wherein thecopolymer obtained by the polymerization in the presence of thepolymerization catalyst is hydrogenation in the presence of thehydrogenation catalyst without newly adding the hydrogenation catalystcomponent.
 9. The preparation process according to claim 7, wherein thediolefin is at least one polyfunctional monomer selected from the groupconsisting of cyclic diene compounds and compounds obtained from atleast two similar or different kinds of residues selected from the groupconsisting of an α-olefin residue, a styrene residue and a cyclic olefinresidue.